Semiconductor Device

Abstract

To provide a technique which can produce a proper number of semiconductor devices from one lead frame.SOLUTION: A semiconductor device comprises: a rectangular-shaped RC-IGBT; an IC chip which is electrically connected to the RC-IGBT; a plurality of control terminals which are electrically connected to the IC chip; a plurality of power terminals which are electrically connected to the RC-IGBT; and a rectangular-shaped sealing resin which covers the RC-IGBT and the IC chip. The aspect ratio of the RC-IGBT is equal to or greater than 1.62. The length in the longitudinal direction of the sealing resin is equal to or less than 44 mm. The rating current of the semiconductor device is equal to or greater than 25 A.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a semiconductor device. [Background technology]

[0002] Power modules, which are semiconductor devices for power generation, are used in various devices, and various power modules have been proposed by various manufacturers. In particular, as a power module for consumer devices such as home appliances, a DIP (Dual Inline Package) type transfer molding power module having terminals made of a lead frame has been proposed (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-106685 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, from the viewpoint of economy, small power modules have been made to have higher current and voltage resistance. In order to achieve higher current and voltage resistance, it is necessary to increase the size of the power chip mounted on the power module. However, when the size of the power chip is increased, the number of power modules that can be produced from one lead frame decreases, which causes a problem of lower productivity.

[0005] Therefore, the present disclosure has been made in consideration of the above-mentioned problems, and has an object to provide a technique that enables an appropriate number of semiconductor devices to be produced from one lead frame. [Means for solving the problem]

[0006] A semiconductor device according to the present disclosure is a semiconductor device comprising: a rectangular RC-IGBT; an IC chip electrically connected to the RC-IGBT; a plurality of control terminals electrically connected to the IC chip; a plurality of power terminals electrically connected to the RC-IGBT; and a rectangular sealing resin covering the RC-IGBT and the IC chip, wherein the plurality of control terminals protrude from one long side of the sealing resin and the plurality of power terminals protrude from the other long side of the sealing resin, an aspect ratio of the RC-IGBT is 1.62 or more, and a longitudinal length of the sealing resin is 44 mm or less, Further comprising two or more wires connecting the RC-IGBT and at least one of the plurality of power terminals, wherein the shape of each of the two or more connection points between the RC-IGBT and the two or more wires in a plan view extends in one direction, and an angle between the one direction and a longitudinal direction of the RC-IGBT is 40° or more and 50° or less. It is. Effect of the Invention

[0007] According to the present disclosure, the aspect ratio of the RC-IGBT is 1.62 or more, the longitudinal length of the sealing resin is 44 mm or less, and the rated current of the semiconductor device is 25 A or more, so that an appropriate number of semiconductor devices can be produced from one lead frame. [Brief description of the drawings]

[0008] [Figure 1] 1 is a plan view illustrating a schematic configuration of a semiconductor device according to a first embodiment. [Diagram 2] 1 is a plan view showing some manufacturing steps of the semiconductor device according to the first embodiment. [Diagram 3] 1 is a plan view illustrating a schematic diagram of an RC-IGBT and an IC chip according to a first embodiment. [Figure 4] 4 is a diagram showing the relationship between the aspect ratio of the RC-IGBT according to the first embodiment and the length X of the sealing resin. FIG. [Diagram 5] FIG. 11 is a plan view illustrating a schematic diagram of an RC-IGBT and an IC chip according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments will be described with reference to the accompanying drawings. The features described in each of the following embodiments are merely examples, and not all features are necessarily required. In addition, in the following description, similar components in multiple embodiments are given the same or similar reference numerals, and different components are mainly described. In addition, in the following description, specific positions and directions such as "upper", "lower", "left", "right", "front" or "back" do not necessarily correspond to positions and directions in actual implementation.

[0010] <Embodiment 1> 1 is a plan view showing a schematic configuration of a semiconductor device 11 according to the present embodiment 1. In the following, the semiconductor device 11 according to the present embodiment 1 will be described as a power module.

[0011] 1 includes an RC-IGBT (Reverse Conductive IGBT) 1, an IC (Integrated Circuit) chip 2, a plurality of control terminals 3, a plurality of power terminals 4, a sealing resin 5, a plurality of wires 6a, 6b, and 6c, and a bootstrap diode 7. For convenience, the outline of the sealing resin 5 is shown by a dashed line in FIG.

[0012] The RC-IGBT1 is a rectangular semiconductor switching element including an IGBT (Insulated Gate Bipolar Transistor) and a free wheel diode provided on one semiconductor substrate. The size of the RC-IGBT1 is smaller than the size of a configuration in which the IGBT and the free wheel diode are provided on different semiconductor substrates. Therefore, when the RC-IGBT1 is used as the power chip of the semiconductor device 11, the size of the power chip and therefore the size of the semiconductor device 11 can be reduced.

[0013] The IC chip 2 is electrically connected to the RC-IGBT1 and controls the RC-IGBT1. For example, the IC chip 2 is electrically connected to the RC-IGBT1 via a wire 6a, and has a function of controlling the RC-IGBT1, such as a function of driving the RC-IGBT1 and a function of protecting the RC-IGBT1 when an abnormality occurs. In the example of FIG. 1, the IC chip 2 includes a high-voltage IC chip 2a electrically connected to three RC-IGBT1 via the wire 6a, and a low-voltage IC chip 2b electrically connected to three RC-IGBT1 via the wire 6a. The high-voltage IC chip 2a and the low-voltage IC chip 2b are mounted on a frame and electrically connected to the frame.

[0014] The IC chip 2 configured in this manner is capable of performing three-phase (U-phase, V-phase, W-phase) AC output by six RC-IGBTs 1. Note that instead of including the high-voltage IC chip 2a and the low-voltage IC chip 2b, the IC chip 2 may be a single IC chip in which these are integrated. Also, the number of RC-IGBTs 1 is not limited to six.

[0015] The control terminals 3 are electrically connected to the IC chip 2. For example, the control terminals 3 may be a frame part electrically connected to the IC chip 2 via the wires 6b, or may be another frame part electrically connected to a frame part (i.e., a die bond part) for mounting the IC chip 2 via the wires 6b. In the example of FIG. 1, bootstrap diodes 7 are mounted on some of the control terminals 3. This configuration makes it possible to save the effort of connecting the semiconductor device 11 according to the first embodiment and the bootstrap diodes at the customer's site.

[0016] The multiple power terminals 4 are electrically connected to the RC-IGBT1. For example, the multiple power terminals 4 may be a frame part electrically connected to the RC-IGBT1 via the wires 6c, or may be another frame part electrically connected to a frame part (i.e., a die bond part) for mounting the RC-IGBT1 via the wires 6c. The power terminals 4 may be integrated with the die bond part on which the RC-IGBT1 is mounted, may be a conductive member ultrasonically bonded to the die bond part, or may be a conductive member electrically connected to the die bond part via wires, solder, or the like.

[0017] 1, for the sake of convenience, the number of wires 6c connected to one RC-IGBT1 is illustrated as one, but the number may be two or more. In the following, an example will be described in which the number of wires 6c connected to one RC-IGBT1 is two or more, and the wire 6c connects the RC-IGBT1 to at least one of the multiple power terminals 4.

[0018] The sealing resin 5 covers the RC-IGBT 1, the IC chip 2, the plurality of wires 6a, 6b, and 6c, the bootstrap diode 7, and the like. The sealing resin 5 has insulating properties, and insulates and protects the RC-IGBT 1, the IC chip 2, the plurality of wires 6a, 6b, and 6c, the bootstrap diode 7, and the like from one another. Hereinafter, in the present embodiment 1, the sealing resin 5 will be described as having a rectangular shape, and the shape of the semiconductor device 11 corresponds to the shape of the sealing resin 5.

[0019] 1, the multiple control terminals 3 protrude from one long side of the sealing resin 5 (the left long side in FIG. 1), and the multiple power terminals 4 protrude from the other long side of the sealing resin 5 (the right long side in FIG. 1). With this configuration, the multiple control terminals 3 and the multiple power terminals 4 are provided on each side of the sealing resin 5. This makes it easier to wire the printed circuit board on which the semiconductor device 1 is mounted, and as a result, it is expected that parasitic inductance and noise will be reduced in the large current path.

[0020] 1, the multiple control terminals 3 are arranged on the opposite side of the IC chip 2 to the RC-IGBT1 in plan view. The multiple power terminals 4 are arranged on the same side of the IC chip 2 as the RC-IGBT1 in plan view. With this configuration, the multiple control terminals 3 can be arranged as close as possible to the IC chip 2, and the multiple power terminals 4 can be arranged as close as possible to the RC-IGBT1. This not only reduces the size of the semiconductor device 11, but also has the associated effect of stabilizing the electrical characteristics by adjusting the inductance of each phase.

[0021] 2 is a plan view showing some manufacturing processes for the semiconductor device 11 according to the present embodiment 1. A frame portion on which an IC chip 2 and the like are mounted, a plurality of control terminals 3, and a plurality of power terminals 4 are included in a lead frame 12, which is a metal plate on which a pattern is formed.

[0022] From the state shown in FIG. 2 in which the tip portions of the control terminals 3 and the tip portions of the power terminals 4 are connected to each other, the lead frame 12 is cut so that these tip portions are separated from each other. Thereafter, the control terminals 3 and the power terminals 4 are bent to complete the semiconductor device 11. In the example shown in FIG. 2, the short side direction of the lead frame 12 corresponds to the long side direction of the semiconductor device 11, and eight semiconductor devices 11 can be produced from one lead frame 12. Note that, as shown in FIG. 2, a screw hole 5a may be provided in the sealing resin 5.

[0023] Here, in the semiconductor device 11 according to the present embodiment 1, the ratio of the long side to the short side of the RC-IGBT1, i.e., the aspect ratio, is 1.62 or more, the longitudinal length of the sealing resin 5 is 44 mm or less, and the rated current of the semiconductor device 11 is 25 A or more.

[0024] Fig. 3 is a plan view showing a schematic diagram of the RC-IGBT 1 and the IC chip 2 according to the present embodiment 1. In Fig. 3, some of the power terminals 4 and the control terminals 3 are omitted from the illustration.

[0025] 3 shows the length X of the sealing resin 5 in the longitudinal direction and the length A of the RC-IGBT 1 in the lateral direction. Equation (1) holds between the length X of the sealing resin 5 in FIG. 3, the length A of the RC-IGBT 1 in the lateral direction, and a length B other than length A that is necessary such as the distance between the RC-IGBTs 1.

[0026] X = 6 × A + B (1)

[0027] Here, we consider optimizing the length X, which is the outer dimension of the semiconductor device 11. The size in the short-side direction of the lead frame 12 allowed by the manufacturing device that conveys the lead frame 12 in Fig. 2 is generally 100 mm. The greater the number of rows of the semiconductor devices 11 in the long-side direction of the lead frame 12, the greater the number of semiconductor devices 11 that can be produced from one lead frame 12, and the better the productivity of the semiconductor devices 11. However, in this case, the filling property of the resin becomes poor in the molding process in which the sealing resin 5 is formed.

[0028] Therefore, the number of rows of semiconductor devices 11 in the longitudinal direction in the short-side direction of lead frame 12 is set to two, as in Fig. 2. In this case, formula (2) must be satisfied between the short-side length W of lead frame 12 per semiconductor device 11, the length B' of the outer frame of lead frame 12 and other necessary components other than length W, and 100 mm which is the size of lead frame 12.

[0029] 2×W+B'≦100 (2)

[0030] By substituting 10 mm, which is the length between the outer frame of the lead frame 12 and the mold for resin molding, into length B' in equation (2), equation (3) holds for the short-side length W of the lead frame 12 per semiconductor device 11.

[0031] W≦45 (3)

[0032] Equation (4) holds between the short-side length W of the lead frame 12 per semiconductor device 11, the long-side length X of one semiconductor device 11, and the clearance S therebetween.

[0033] X+S=W (4)

[0034] When 1 mm is substituted for the clearance S in formula (4), formula (5) is established for the length X of one semiconductor device 11, that is, the length X of the sealing resin 5.

[0035] X≦44 (5)

[0036] For length B in formula (1), 20 mm is substituted, which is the sum of the insulation distances at three locations between the four power terminals 4, the space for forming the solder fillet under the RC-IGBT1, the length of the electrodes, and the dimension of the screw hole 5a in Fig. 2. Fig. 4 is a diagram showing the relationship between the aspect ratio of the RC-IGBT1 in this case and the length X of the sealing resin 5. Note that, when the length of the RC-IGBT1 in the longitudinal direction is constant, the shorter the length A of the RC-IGBT1 in the transverse direction, the larger the aspect ratio of the RC-IGBT1 becomes.

[0037] 4, when the chip size is large, the aspect ratio of the RC-IGBT1 corresponding to the length X of the sealing resin 5 of 44 mm is 1.62. For this reason, it is preferable to set the length W of the lead frame 12 per semiconductor device 11 to 45 mm or less, the length X of the sealing resin 5 to 44 mm or less, and the aspect ratio of the RC-IGBT1 to 1.62 or more. With this configuration, it is possible to increase the number of semiconductor devices 11 that can be produced from one lead frame 12 as much as possible while taking into consideration the tolerance of the manufacturing equipment that transports the lead frame 12. As a result, it is possible to improve productivity while suppressing capital investment.

[0038] 3 shows wires 6a connecting the RC-IGBT1 and the IC chip 2. The wires 6a are thin wires made of metal such as aluminum and copper. Two or more wires 6a are arranged in the short direction of each RC-IGBT1 and connected to the part of each RC-IGBT1 on the IC chip 2 side.

[0039] 3, two or more wires 6a and two or more connection points to the RC-IGBT1 are arranged along the short side direction of the RC-IGBT1, so that the effective area of ​​the RC-IGBT1, which has a large aspect ratio, can be fully utilized. Note that, "two or more connection points are arranged along the short side direction of the RC-IGBT1" means, for example, that the angle between the arrangement direction of the two or more connection points and the short side direction of the RC-IGBT1 is 5° or less.

[0040] 3 also shows the wire 6c in FIG. 1 connected to the power terminal 4 and the connection point 1a with the RC-IGBT 1. A thick wire made of metal is used for the wire 6c. The number of wires 6c connected to the RC-IGBT 1 is preferably two or more, and more preferably three or more as shown in FIG. 3.

[0041] The two or more wires 6c are connected to the parts of the RC-IGBTs 1 that are far from the IC chip 2, while being arranged in the longitudinal direction of each RC-IGBT 1. As a result, as shown in FIG. 3, two or more connection points 1a between the RC-IGBTs 1 and the two or more wires 6c are arranged along the longitudinal direction of the RC-IGBTs 1. The arrangement of the two or more connection points 1a along the longitudinal direction of the RC-IGBTs 1 means that the angle between the arrangement direction of the two or more connection points 1a and the longitudinal direction of the RC-IGBTs 1 is 5° or less. On the other hand, the two or more connection points between the RC-IGBTs 1 and the two or more wires 6c are not arranged along the short side direction of the RC-IGBTs 1. With this configuration, it is possible to make the length W (sometimes called one-pitch width) of the lead frame 12 per one semiconductor device 11 45 mm or less.

[0042] Moreover, the shape of the connection point 1a in plan view extends in one direction. In the example of FIG. 3, the shape of the connection point 1a in plan view is an ellipse extending in one direction, which is the longitudinal direction, and the angle between the longitudinal direction of the connection point 1a and the longitudinal direction of the RC-IGBT1 is 40° or more and 50° or less, and preferably 45°. With this configuration, it is possible to ensure the insulation distance between the wires 6c while shortening the short-side length A of the RC-IGBT1. This is particularly effective in a configuration in which the length X of one semiconductor device 11 (i.e., the length X of the sealing resin 5) is relatively small, such as 44 mm or less, and an RC-IGBT1 with an aspect ratio of 1.62 or more is mounted.

[0043] <Embodiment 2> 5 is a plan view showing a schematic diagram of the RC-IGBT 1 and the IC chip 2 according to the present embodiment 2. In the following, among the components according to the present embodiment 2, the components that are the same as or similar to the components described above are given the same or similar reference numerals, and different components will be mainly described.

[0044] In the second embodiment, the IC chip 2 has a rectangular shape, and the length of the short side of the RC-IGBT1 is 1 / 3 or less of the length of the long side of the IC chip 2. The IC chip 2 includes a bonding pad 2c on the RC-IGBT1 side, and the RC-IGBT1 includes a gate pad 1b on the IC chip 2 side, and the wire 6a connects the bonding pad 2c and the gate pad 1b. When driving six RC-IGBT1s by the high-voltage IC chip 2a and the low-voltage IC chip 2b as in the first embodiment, two sets of the configuration of FIG. 5 are provided.

[0045] In a semiconductor device that is transfer molded, if the wires 6a are long, they are likely to be swept away when resin is injected in the molding process, which may cause the wires 6a to become detached and cause a short circuit. In contrast, according to the above configuration of the second embodiment, the distance between the RC-IGBT 1 and the IC chip 2 can be shortened, which allows the wires 6a to be shortened and the short circuit to be suppressed.

[0046] <Modification> In the first and second embodiments, the material of the RC-IGBT1 may be ordinary silicon or a wide band gap semiconductor. Wide band gap semiconductors include, for example, silicon carbide (SiC), gallium nitride (GaN), diamond, and the like. The RC-IGBT1 including the wide band gap semiconductor has high voltage resistance and low loss, so that the RC-IGBT1 chip size can be reduced, and as a result, the semiconductor device 11 can be made smaller. In addition, since the heat resistance of the RC-IGBT1 chip can be increased, the size of the fins required for heat dissipation of the semiconductor device 11 can be expected to be reduced.

[0047] It should be noted that the embodiments and modifications may be freely combined, and the embodiments and modifications may be modified or omitted as appropriate. [Explanation of symbols]

[0048] 1 RC-IGBT, 1a connection point, 1b gate pad, 2 IC chip, 2c bonding pad, 3 control terminal, 4 power terminal, 5 sealing resin, 6a, 6c wires, 11 semiconductor device.

Claims

1. A semiconductor device comprising: A rectangular RC-IGBT; an IC chip electrically connected to the RC-IGBT; A plurality of control terminals electrically connected to the IC chip; A plurality of power terminals electrically connected to the RC-IGBT; a rectangular sealing resin that covers the RC-IGBT and the IC chip; Equipped with the control terminals protrude from one long side of the sealing resin, the plurality of power terminals protrude from the other long side of the sealing resin, The aspect ratio of the RC-IGBT is 1.62 or more; The length of the sealing resin in the longitudinal direction is 44 mm or less, Further comprising two or more wires connecting the RC-IGBT and at least one of the plurality of power terminals; each of the two or more connection points between the RC-IGBT and the two or more wires has a shape in a plan view that extends in one direction; The angle between the one direction and a longitudinal direction of the RC-IGBT is 40° or more and 50° or less.

2. 2. The semiconductor device according to claim 1, the two or more connection points between the RC-IGBT and the two or more wires are arranged along a longitudinal direction of the RC-IGBT.

3. 2. The semiconductor device according to claim 1, The IC chip has a rectangular shape, The length of the RC-IGBT in the short direction is 1 / 3 or less of the length of the IC chip in the long direction, the IC chip includes a bonding pad on the RC-IGBT side; The RC-IGBT includes a gate pad on the IC chip side, The semiconductor device further comprises a wire connecting the bonding pad and the gate pad.

4. 4. The semiconductor device according to claim 1, A semiconductor device, wherein the material of the RC-IGBT includes a wide band gap semiconductor.

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