Semiconductor equipment

Abstract

The present invention provides a semiconductor device that suppresses the temperature rise of heat-generating components. [Solution] The semiconductor device 10 comprises a substrate 15, semiconductor elements 21, 22, 23, and 24 connected to the substrate surface 150, a conductive P terminal 61 connected to the substrate 15, and a resistive element 750 connected to the substrate 15 that generates heat when current flows through it. When the resistive element 750 is projected in the thickness direction DT of the substrate 15, the projected resistive element 750 overlaps with the P terminal 61.

Description

Technical Field

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

Background Art

[0002] Conventionally, as described in Patent Document 1, a semiconductor device including a printed circuit board, a semiconductor chip, an interposer, and a snubber circuit is known. The semiconductor chip is connected to the printed circuit board via the interposer. The snubber circuit is disposed on the surface of the printed circuit board opposite to the semiconductor chip.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the semiconductor device described in Patent Document 1 is driven, heat-generating components such as the semiconductor chip and the snubber circuit generate heat. The amount of heat generated in the semiconductor chip is larger than the amount of heat generated in the heat-generating components. Further, when the heat-generating components are projected in the thickness direction of the printed circuit board, the projected heat-generating components overlap with the semiconductor chip. As a result, the heat generated in the semiconductor chip is likely to be conducted to the heat-generating components via the interposer and the printed circuit board. Therefore, since the temperature of the heat-generating components is likely to rise, the thermal stress applied to the heat-generating components is likely to increase. Therefore, in the semiconductor device described in Patent Document 1, heat-generating components such as the snubber circuit are likely to be damaged.

[0005] An object of the present disclosure is to provide a semiconductor device that suppresses a temperature rise of heat-generating components.

Means for Solving the Problems

[0006] The invention described in claim 1 is a semiconductor device comprising a substrate (15), semiconductor elements (21, 22, 23, 24) connected to the surface (150) of the substrate, conductive terminals (61, 611, 612) connected to the substrate, and heat-generating components (750, 751, 752) connected to the substrate that generate heat when current flows through them, wherein when the heat-generating components are projected in the thickness direction (DT) of the substrate, the projected heat-generating components overlap with the terminals.

[0007] Furthermore, the invention described in claim 17 is a semiconductor device comprising a substrate (15), semiconductor elements (21, 22, 23, 24) connected to the surface (150) of the substrate, a heat dissipation member (51) connected to the semiconductor elements on the side opposite to the substrate and extending in a direction perpendicular to the thickness direction (DT) of the substrate, and a heat-generating component (750) connected to the back surface (152) of the substrate and generating heat when current flows through it, wherein when the heat-generating component is projected in the thickness direction, the projected heat-generating component overlaps with the heat dissipation member.

[0008] Furthermore, the invention described in claim 22 is a semiconductor device comprising a substrate (15), semiconductor elements (21, 22, 23, 24) connected to the surface (150) of the substrate, conductive terminals (61, 611, 612) connected to the surface, and heat-generating components (750, 751, 752) connected to the surface and generating heat when current flows through them, wherein the distance from the heat-generating components to the terminals (Drp0, Drp1, Drp2) in a direction perpendicular to the thickness direction (DT) of the substrate is shorter than the distance from the heat-generating components to the semiconductor elements (Drs0, Drs1, Drs2) in a direction perpendicular to the thickness direction.

[0009] As a result, heat generated in the heat-generating component is easily conducted to the terminals. Therefore, heat generated in the heat-generating component is easily dissipated. Furthermore, heat generated in the semiconductor element is less likely to be conducted to the heat-generating component. Consequently, the temperature rise of the heat-generating component is suppressed.

[0010] The reference numerals in parentheses attached to each component indicate an example of the correspondence between that component and the specific components described in the embodiments described later. [Brief explanation of the drawing]

[0011] [Figure 1] A top view of the semiconductor device of the first embodiment. [Figure 2] Cross-sectional view along line II-II in Figure 1. [Figure 3] Cross-sectional view along line III-III in Figure 1. [Figure 4] Circuit diagram of a semiconductor device. [Figure 5] Cross-sectional view of the semiconductor device of Comparative Example 1. [Figure 6] A diagram showing the temperature distribution of the semiconductor device in Comparative Example 1. [Figure 7] A diagram showing the temperature of the resistive element in the semiconductor device of Comparative Example 1 and the first embodiment. [Figure 8] A diagram showing the temperature distribution of the semiconductor device of the first embodiment. [Figure 9] Cross-sectional view of the semiconductor device of Comparative Example 2. [Figure 10] A top view of the semiconductor device of the second embodiment. [Figure 11] Figure 10 shows a cross-sectional view along line XI-XI. [Figure 12] Figure 10 shows a cross-sectional view along line XII-XII. [Figure 13] A top view of the semiconductor device of the third embodiment. [Figure 14] Figure 13 shows a cross-sectional view along line XIV-XIV. [Figure 15] A top view of the semiconductor device of the fourth embodiment. [Figure 16] Circuit diagram of a semiconductor device. [Figure 17] A top view of the semiconductor device of the fifth embodiment. [Figure 18] Cross-sectional view of the semiconductor device according to the sixth embodiment. [Figure 19] Cross-sectional view of the semiconductor device according to the seventh embodiment. [Figure 20] Cross-sectional view of the semiconductor device according to the eighth embodiment. [Figure 21] Cross-sectional view of the semiconductor device of the ninth embodiment. [Figure 22] Cross-sectional view of the semiconductor device of the tenth embodiment. [Figure 23] Cross-sectional view of the semiconductor device of the eleventh embodiment. [Figure 24] Cross-sectional view of the semiconductor device of the twelfth embodiment. [Figure 25] Cross-sectional view of the semiconductor device of the thirteenth embodiment. [Figure 26] Cross-sectional view of the semiconductor device of the fourteenth embodiment. [Figure 27] Cross-sectional view of the semiconductor device of the fifteenth embodiment. [Figure 28] Circuit diagram of the semiconductor device. [Figure 29] Top view of the semiconductor device of the sixteenth embodiment. [Figure 30] Cross-sectional view taken along line XXX-XXX of FIG. 29. [[ID=…]] Please note that the content you provided seems to be incomplete. The tags from `` to the end are not fully translated in the above content, but the translation rule requires maintaining the original tags unchanged. If you want a complete translation, please provide the full and correct content. [Figure 31] Cross-sectional view taken along line XXXI-XXXI of FIG. 29. [Figure 32] Top view of the semiconductor device of the seventeenth embodiment. [[ID=3…]] (The content continues, but due to the incomplete nature of the input, the full translation cannot be provided accurately. The above is the translation based on the existing content.) [Figure 33] Cross-sectional view taken along line XXXIII-XXXIII of FIG. 32.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, the embodiments will be described with reference to the drawings. In the following embodiments, parts that are identical or equivalent to each other are denoted by the same reference numerals, and their descriptions are omitted.

[0013] (First Embodiment) The semiconductor device of this embodiment suppresses the temperature rise of heat-generating components. Specifically, as shown in Figures 1 to 4, the semiconductor device 10 comprises a substrate 15, a first semiconductor element 21, a bonding material 31 for the first semiconductor element, a first gate wiring 41, a second semiconductor element 22, a bonding material 32 for the second semiconductor element, a second gate wiring 42, and a first heat dissipation member 51. The semiconductor device 10 also comprises a third semiconductor element 23, a bonding material 33 for the third semiconductor element, a third gate wiring 43, a fourth semiconductor element 24, a bonding material 34 for the fourth semiconductor element, a fourth gate wiring 44, and a second heat dissipation member 52. Furthermore, the semiconductor device 10 comprises a P terminal 61, a bonding material 71 for the P terminal, an O terminal 62, a bonding material 72 for the O terminal, an N terminal 63, a bonding material 73 for the N terminal, a snubber circuit 75, a sealing resin 80, a heat conductive member 85, and a cooler 90.

[0014] The substrate 15 is a printed circuit board, formed from a glass epoxy resin such as FR4. FR4 is an abbreviation for Flame Retardant Type 4. Furthermore, in the following description, the thickness direction of the substrate 15 will simply be referred to as the thickness direction DT.

[0015] Furthermore, as shown in Figures 1 to 3, the substrate 15 has a substrate surface 150 and a substrate back surface 152. The substrate surface 150 is one side of the substrate 15 in the thickness direction DT. The substrate back surface 152 is the other side of the substrate 15 in the thickness direction DT, and is the side of the substrate 15 opposite to the substrate surface 150.

[0016] The first semiconductor device 21 is, for example, a MOSFET made of Si or SiC. MOSFET stands for Metal-Oxide-Semiconductor Field-Effect Transistor.

[0017] Furthermore, as shown in Figures 2 and 3, the source electrode of the first semiconductor element 21 is connected to the substrate surface 150 via a bonding material 31 for the first semiconductor element. The gate electrode of the first semiconductor element 21 is connected to the first gate wiring 41 formed on the substrate 15 via the bonding material 31 for the first semiconductor element. The bonding material 31 for the first semiconductor element is, for example, solder or sintered silver.

[0018] The second semiconductor element 22 is, for example, a MOSFET made of Si or SiC. The source electrode of the second semiconductor element 22 is connected to the substrate surface 150 via the bonding material 32 for the second semiconductor element. Furthermore, as shown in Figure 4, the second semiconductor element 22 is connected in parallel to the first semiconductor element 21. Returning to Figures 2 and 3, the gate electrode of the second semiconductor element 22 is connected to the second gate wiring 42 formed on the substrate 15 via the bonding material 32 for the second semiconductor element. The bonding material 32 for the second semiconductor element is, for example, solder or sintered silver.

[0019] The first heat dissipation member 51 dissipates heat generated by the first semiconductor element 21 and the second semiconductor element 22 to the outside. The first heat dissipation member 51 is, for example, an insulating circuit board and has a first heat dissipation section 510, a first insulating section 512, and a second heat dissipation section 514.

[0020] The first heat dissipation section 510 is made of copper or the like. As a result, the first heat dissipation section 510 is conductive and has a relatively high thermal conductivity. The first heat dissipation section 510 is also formed in a plate shape. Furthermore, the first heat dissipation section 510 is connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22.

[0021] The first insulating portion 512 is formed of ceramics or the like. As a result, the first insulating portion 512 has electrical insulating properties. The first insulating portion 512 is also formed in a plate shape. Furthermore, the first insulating portion 512 is connected in the thickness direction DT to the side of the first heat dissipation portion 510 that is opposite to the first semiconductor element 21 and the second semiconductor element 22.

[0022] The second heat dissipation section 514 is made of copper or the like. As a result, the second heat dissipation section 514 is conductive and has a relatively high thermal conductivity. The second heat dissipation section 514 is also formed in a plate shape. Furthermore, the second heat dissipation section 514 is connected to the side of the first insulating section 512 opposite to the first heat dissipation section 510 in the thickness direction DT. Therefore, when the first semiconductor element 21 and the second semiconductor element 22 generate heat, the heat from the first semiconductor element 21 and the second semiconductor element 22 is conducted to the first heat dissipation member 51 and dissipated.

[0023] The third semiconductor element 23 is, for example, a MOSFET made of Si or SiC. The source electrode of the third semiconductor element 23 is connected to the substrate surface 150 via a bonding material 33 for the third semiconductor element. The gate electrode of the third semiconductor element 23 is connected to a third gate wiring 43 formed on the substrate 15 via the bonding material 33 for the third semiconductor element. The bonding material 33 for the third semiconductor element is, for example, solder or sintered silver.

[0024] The fourth semiconductor element 24 is, for example, a MOSFET made of Si or SiC. The source electrode of the fourth semiconductor element 24 is connected to the substrate surface 150 via the bonding material 34 for the fourth semiconductor element. Furthermore, as shown in Figure 4, the fourth semiconductor element 24 is connected in parallel to the third semiconductor element 23. Returning to Figures 2 and 3, the gate electrode of the fourth semiconductor element 24 is connected to the fourth gate wiring 44 formed on the substrate 15 via the bonding material 34 for the fourth semiconductor element. The bonding material 34 for the fourth semiconductor element is, for example, solder or sintered silver.

[0025] The second heat dissipation member 52 dissipates heat generated by the third semiconductor element 23 and the fourth semiconductor element 24 to the outside. The second heat dissipation member 52 is, for example, an insulating circuit board having a third heat dissipation section 520, a second insulating section 522, and a fourth heat dissipation section 524.

[0026] The third heat dissipation section 520 is made of copper or the like. As a result, the third heat dissipation section 520 is conductive and has a relatively high thermal conductivity. The third heat dissipation section 520 is also formed in a plate shape. Furthermore, the third heat dissipation section 520 is connected to the drain electrode of the third semiconductor element 23 and the drain electrode of the fourth semiconductor element 24.

[0027] The second insulating portion 522 is made of ceramics or the like. As a result, the second insulating portion 522 has electrical insulating properties. The second insulating portion 522 is also formed in a plate shape. Furthermore, the second insulating portion 522 is connected in the thickness direction DT to the side of the third heat dissipation portion 520 that is opposite to the third semiconductor element 23 and the fourth semiconductor element 24.

[0028] The fourth heat dissipation section 524 is made of copper or the like. As a result, the fourth heat dissipation section 524 is conductive and has a relatively high thermal conductivity. The fourth heat dissipation section 524 is also formed in a plate shape. Furthermore, the fourth heat dissipation section 524 is connected to the side of the second insulating section 522 opposite to the third heat dissipation section 520 in the thickness direction DT. Therefore, when the third semiconductor element 23 and the fourth semiconductor element 24 generate heat, the heat from the third semiconductor element 23 and the fourth semiconductor element 24 is conducted to the second heat dissipation member 52 and dissipated.

[0029] The P terminal 61 is made of a metal or the like and is therefore conductive. Furthermore, the P terminal 61 is formed, for example, in a plate shape. In addition, as shown in Figure 2, the P terminal 61 is connected to the substrate surface 150 in the thickness direction DT via a P terminal bonding material 71. The P terminal bonding material 71 is, for example, solder or sintered silver. The P terminal 61 is also connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22 via the P terminal bonding material 71, the vias and wiring layers formed on the substrate 15, the bonding material, and the first heat dissipation section 510. Therefore, one end of the P terminal 61 is connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22, as shown in Figure 4.

[0030] Furthermore, the other end of terminal P 61 is connected to one end of the power supply capacitor 92. The power supply capacitor 92 is located outside the semiconductor device 10. The power supply capacitor 92 is also charged by power from a power source (not shown). Furthermore, the power supply capacitor 92 supplies the charged power to the semiconductor device 10 via terminal P 61.

[0031] The O terminal 62 is made of a metal or the like and is therefore conductive. Furthermore, the O terminal 62 is formed, for example, in a plate shape. In addition, as shown in Figures 2 and 3, the O terminal 62 is connected to the substrate surface 150 in the thickness direction DT via an O terminal bonding material 72. The O terminal bonding material 72 is, for example, solder or sintered silver.

[0032] Furthermore, terminal O 62 is connected to the source electrode of the first semiconductor element 21 via the bonding material 72 for terminal O, the vias and wiring layers formed on the substrate 15, and the bonding material 31 for the first semiconductor element. In addition, terminal O 62 is connected to the source electrode of the second semiconductor element 22 via the bonding material 72 for terminal O, the vias and wiring layers formed on the substrate 15, and the bonding material 32 for the second semiconductor element. Furthermore, terminal O 62 is connected to the drain electrode of the third semiconductor element 23 and the drain electrode of the fourth semiconductor element 24 via the bonding material 72 for terminal O, the vias and wiring layers formed on the substrate 15, the bonding material, and the third heat dissipation section 520. Therefore, as shown in Figure 4, one end of terminal O 62 is connected to the source electrode of the first semiconductor element 21, the source electrode of the second semiconductor element 22, the drain electrode of the third semiconductor element 23, and the drain electrode of the fourth semiconductor element 24.

[0033] Furthermore, the other end of terminal O 62 is connected to a load (not shown). Terminal O 62 also outputs current to the load in accordance with the on / off states of the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24.

[0034] Returning to Figure 3, the N terminal 63 is connected to the substrate surface 150 in the thickness direction DT via the N terminal bonding material 73. The N terminal bonding material 73 is, for example, solder or sintered silver. Furthermore, the N terminal 63 is connected to the source electrode of the third semiconductor element 23 via the N terminal bonding material 73, the vias and wiring layers formed on the substrate 15, and the third semiconductor element bonding material 33. Also, the N terminal 63 is connected to the source electrode of the fourth semiconductor element 24 via the N terminal bonding material 73, the vias and wiring layers formed on the substrate 15, and the fourth semiconductor element bonding material 34. Therefore, as shown in Figure 4, one end of the N terminal 63 is connected to the source electrode of the third semiconductor element 23 and the source electrode of the fourth semiconductor element 24. Furthermore, the other end of the N terminal 63 is connected to the other end of the supply capacitor 92.

[0035] The snubber circuit 75 receives power from the power supply capacitor 92 and supplies the received power into the semiconductor device 10. Compared to the case where power is supplied to the semiconductor device 10 from the power supply capacitor 92, the snubber circuit 75 shortens the current path, thus suppressing the increase in inductance. For example, the snubber circuit 75 has a resistive element 750 and a capacitive element 760.

[0036] The resistive element 750 corresponds to a heat-generating component; it is an electrical resistor that generates heat when current flows through it. Furthermore, as shown in Figures 1 and 2, the resistive element 750 is connected to the back surface 152 of the substrate in the thickness direction DT. In addition, one end of the resistive element 750 is connected to the P terminal 61 via vias and wiring layers (not shown) formed on the substrate 15. When the resistive element 750 is projected in the thickness direction DT, the projected resistive element 750 overlaps with the P terminal 61. Furthermore, when the resistive element 750 is projected in the thickness direction DT, the projected resistive element 750 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24.

[0037] Furthermore, one end of the resistive element 750 is connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22 via vias and wiring layers (not shown) formed on the substrate 15. In addition, as shown in Figure 4, the resistive element 750 is connected in parallel to the first semiconductor element 21 and the second semiconductor element 22.

[0038] The capacitive element 760 is a capacitor and, as shown in Figures 1 and 3, is connected to the back surface 152 of the substrate in the thickness direction DT. One end of the capacitive element 760 is connected to the other end of the resistive element 750 via vias and wiring layers (not shown) formed on the substrate 15. Furthermore, as shown in Figure 4, the capacitive element 760 is connected in series with the resistive element 750.

[0039] Returning to Figures 1 and 3, the other end of the capacitive element 760 is connected to the source electrode of the third semiconductor element 23 and the source electrode of the fourth semiconductor element 24 via vias and wiring layers (not shown) formed on the substrate 15. Furthermore, as shown in Figure 4, the capacitive element 760 is connected in parallel to the third semiconductor element 23 and the fourth semiconductor element 24.

[0040] Returning to Figures 2 and 3, the sealing resin 80 corresponds to the covering portion and is made of resin. The sealing resin 80 covers the substrate 15, the first semiconductor element 21, the bonding material for the first semiconductor element 31, and the first gate wiring 41. Furthermore, the sealing resin 80 covers the second semiconductor element 22, the bonding material for the second semiconductor element 32, the second gate wiring 42, and the first heat dissipation member 51. The sealing resin 80 also covers the third semiconductor element 23, the bonding material for the third semiconductor element 33, the third gate wiring 43, the fourth semiconductor element 24, the bonding material for the fourth semiconductor element 34, the fourth gate wiring 44, and the second heat dissipation member 52. Furthermore, the sealing resin 80 covers a portion of the P terminal 61, the bonding material for the P terminal 71, a portion of the O terminal 62, the bonding material for the O terminal 72, a portion of the N terminal 63, and the bonding material for the N terminal 73.

[0041] Furthermore, the back surface 152 of the substrate is exposed from the sealing resin 80. In addition, the side of the second heat dissipation section 514 opposite to the first insulating section 512 is exposed from the sealing resin 80. Also, the side of the fourth heat dissipation section 524 opposite to the second insulating section 522 is exposed from the sealing resin 80. Furthermore, the P terminal 61, O terminal 62, and N terminal 63 protrude from the sealing resin 80 in a direction perpendicular to the thickness direction DT.

[0042] The heat conductive member 85 is made of TIM. Therefore, the thermal conductivity of the heat conductive member 85 is relatively high. TIM stands for Thermal Interface Material.

[0043] Furthermore, the heat conductive member 85 is formed in a gel-like, sheet-like, or clay-like state. In addition, the heat conductive member 85 is connected in the thickness direction DT to the exposed surface of the second heat dissipation section 514 and the exposed surface of the fourth heat dissipation section 524. Furthermore, the heat conductive member 85 is connected in the thickness direction DT to the surface of the sealing resin 80 adjacent to the exposed surface of the second heat dissipation section 514 and the exposed surface of the fourth heat dissipation section 524. Furthermore, when the heat conductive member 85 is projected in the thickness direction DT, the projected heat conductive member 85 overlaps with the P terminal 61 and the resistive element 750. Furthermore, when the heat conductive member 85 is projected in the thickness direction DT, the projected heat conductive member 85 overlaps with the first semiconductor element 21 and the second semiconductor element 22. Furthermore, when the heat conductive member 85 is projected in the thickness direction DT, the projected heat conductive member 85 overlaps with the third semiconductor element 23 and the fourth semiconductor element 24.

[0044] The cooler 90 is positioned on the substrate surface 150 side within the semiconductor device 10. The cooler 90 is also connected to the heat conductive member 85 on the side opposite to the sealing resin 80. This allows the cooler 90 to cool the inside of the semiconductor device 10. Furthermore, when the cooler 90 is projected in the thickness direction DT, the projected cooler 90 overlaps with the P terminal 61, the resistive element 750, and the heat conductive member 85. This makes the P terminal 61 easier to cool. The cooler 90 may be, for example, a pipe, and the inside of the semiconductor device 10 is cooled by the flow of air through the cooler 90. Alternatively, the cooler 90 may be, for example, a fin, corrugated fin, or pin fin, made of a metal such as copper or aluminum, or a material with relatively high thermal conductivity such as graphite, consisting of multiple flat plates arranged in a row.

[0045] As described above, the semiconductor device 10 of the first embodiment is configured as described. Next, the suppression of the temperature rise of the heat-generating resistive element 750 by the semiconductor device 10 will be explained.

[0046] Here, as shown in Figure 5, in Comparative Example 1, when the resistive element 750 is projected in the thickness direction DT, the projected resistive element 750 overlaps with the first semiconductor element 21 and the second semiconductor element 22. Furthermore, it is assumed that the first semiconductor element 21, the second semiconductor element 22, and the resistive element 750 are in operation. In this case, the heat generated in the first semiconductor element 21 and the second semiconductor element 22 is easily conducted to the resistive element 750 through the bonding material 31 for the first semiconductor element, the bonding material 32 for the second semiconductor element, and the substrate 15. As a result, the temperature of the resistive element 750 tends to rise, and as shown in Figures 6 and 7, the temperature of the resistive element 750 when the apparatus of Comparative Example 1 is in operation is approximately 250°C.

[0047] In contrast, in the semiconductor device 10 of this embodiment, as shown in Figure 2, when the resistive element 750 is projected in the thickness direction DT, the projected resistive element 750 overlaps with the P terminal 61. Also, when the resistive element 750 is projected in the thickness direction DT, the projected resistive element 750 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24.

[0048] As a result, the heat generated in the resistive element 750 is easily conducted to the P terminal 61. Therefore, the heat generated in the resistive element 750 is easily dissipated. Furthermore, the heat generated in the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24 is less likely to be conducted to the resistive element 750. Consequently, the temperature rise of the heat-generating component, the resistive element 750, is suppressed.

[0049] Furthermore, the semiconductor device 10 of the first embodiment also provides the following effects.

[0050] [1-1] The P terminal 61 is connected to the substrate surface 150. The resistive element 750 is connected to the substrate back surface 152. The semiconductor device 10 further includes a cooler 90. The cooler 90 is located on the substrate surface 150 side and cools the P terminal 61. When the cooler 90 is projected in the thickness direction DT, the projected cooler 90 overlaps with the P terminal 61 and the resistive element 750.

[0051] As a result, the P terminal 61 is more easily cooled. Therefore, the heat generated in the resistive element 750 is more easily transferred to the cooler 90 via the P terminal 61. Consequently, as shown in Figures 7 and 8, the temperature of the resistive element 750 when the semiconductor device 10 of this embodiment is in operation is approximately 160°C. Thus, the temperature of the resistive element 750 is 90°C lower compared to the device of Comparative Example 1. Consequently, the temperature rise of the resistive element 750 is suppressed.

[0052] Here, as described in Japanese Patent Publication No. 5558645, in Comparative Example 2, as shown in Figure 9, the P terminal 61 is connected to the first heat dissipation unit 510 via a bonding material, and the substrate 15 is also connected to the P terminal 61. Furthermore, in the apparatus of Comparative Example 2, the resistive element 750 is connected to the side of the substrate 15 opposite to the P terminal 61. Also, in the apparatus of Comparative Example 2, when the cooler 90 is projected in the thickness direction DT, the projected cooler 90 does not overlap with the P terminal 61 and the resistive element 750. Therefore, the heat path from the resistive element 750 to the cooler 90 via the P terminal 61 is relatively long. Consequently, in the apparatus of Comparative Example 2, the temperature of the resistive element 750 tends to rise.

[0053] In contrast, in the semiconductor device 10 of the first embodiment, when the cooler 90 is projected in the thickness direction DT, the projected cooler 90 overlaps with the P terminal 61 and the resistive element 750. As a result, the heat path from the resistive element 750 to the cooler 90 via the P terminal 61 is relatively short. Therefore, the temperature rise of the resistive element 750 is suppressed compared to the apparatus of Comparative Example 2.

[0054] [1-2] The semiconductor device 10 comprises a sealing resin 80 and a heat conductive member 85. The sealing resin 80 covers the substrate 15, the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24, and the P terminal 61, etc. The heat conductive member 85 is connected to the sealing resin 80 and the cooler 90. When the P terminal 61 is projected in the thickness direction DT, the projected P terminal 61 overlaps with the heat conductive member 85.

[0055] As a result, heat from the P terminal 61 is more easily transferred to the cooler 90 via the sealing resin 80 and the heat conductive member 85. Therefore, the heat generated in the resistive element 750 is more easily transferred to the cooler 90 via the P terminal 61, the sealing resin 80, and the heat conductive member 85. Consequently, the heat generated in the resistive element 750 is more easily dissipated, and the temperature rise of the resistive element 750 is suppressed.

[0056] (Second Embodiment) In the second embodiment, the configurations of the P terminal 61, the N terminal 63, and the resistor element 750 differ from those of the first embodiment. Otherwise, it is the same as the first embodiment.

[0057] Specifically, as shown in Figures 10 and 11, the P terminal 61 is connected to the back surface 152 of the substrate via a bonding material 71 for the P terminal, instead of to the substrate surface 150, in a vertical direction (DT) in the thickness direction. The N terminal 63 is connected to the back surface 152 of the substrate via a bonding material 73 for the N terminal, instead of to the substrate surface 150, in a vertical direction (DT) in the thickness direction, instead of to the substrate surface 150, in a vertical direction (DT) in the thickness direction, instead of to the substrate back surface 152 as shown in Figure 11.

[0058] As described above, the semiconductor device 10 of the second embodiment is configured as described. This second embodiment also provides the same effects as the first embodiment.

[0059] (Third embodiment) In the third embodiment, the form of the capacitive element 760 differs from that of the second embodiment. Otherwise, it is the same as in the second embodiment.

[0060] Specifically, as shown in Figures 13 and 14, the capacitive element 760 is connected to the substrate surface 150 and in the thickness direction DT, instead of to the substrate back surface 152.

[0061] As described above, the semiconductor device 10 of the third embodiment is configured as described. This third embodiment also provides the same effects as the second embodiment.

[0062] (Fourth Embodiment) In the fourth embodiment, the semiconductor device 10 is equipped with a first P terminal 611 and a second P terminal 612 instead of the P terminal 61. Furthermore, the configuration of the snubber circuit 75 of the semiconductor device 10 differs from that of the first embodiment. Other than these differences, it is the same as the first embodiment.

[0063] The first P terminal 611 corresponds to the P terminal 61 and is made of metal or the like, and is therefore conductive. Furthermore, as shown in Figures 15 and 16, the first P terminal 611 is formed, for example, in a plate shape. In addition, the first P terminal 611 is connected to the substrate surface 150 in the thickness direction DT via a bonding material. The first P terminal 611 is also connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22 via the bonding material, vias and wiring layers formed on the substrate 15, and the first heat dissipation part 510. Therefore, one end of the first P terminal 611 is connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22, as shown in Figure 16. Furthermore, the other end of the first P terminal 611 is connected to one end of the supply capacitor 92.

[0064] The second P terminal 612 is made of metal or the like and is therefore conductive. Furthermore, as shown in Figures 15 and 16, the second P terminal 612 is formed, for example, in a plate shape. The second P terminal 612 is connected to the substrate surface 150 in the thickness direction DT via a bonding material. The second P terminal 612 is also connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22 via the bonding material, vias and wiring layers formed on the substrate 15, and the first heat dissipation section 510. Therefore, one end of the second P terminal 612 is connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22, as shown in Figure 16. Furthermore, the second P terminal 612 is connected in parallel to the first P terminal 611. The other end of the second P terminal 612 is connected to one end of the supply capacitor 92.

[0065] The snubber circuit 75 has a first resistive element 751, a second resistive element 752, a first capacitive element 761, and a second capacitive element 762, as shown in Figure 15, instead of the resistive element 750 and the capacitive element 760.

[0066] The first resistive element 751 corresponds to a heat-generating component; it is an electrical resistor that generates heat when current flows through it. The first resistive element 751 is connected to the back surface 152 of the substrate in the thickness direction DT. Furthermore, one end of the first resistive element 751 is connected to the first P terminal 611 via vias and wiring layers (not shown) formed on the substrate 15. When the first resistive element 751 is projected in the thickness direction DT, the projected first resistive element 751 overlaps with the first P terminal 611. Furthermore, when the first resistive element 751 is projected in the thickness direction DT, the projected first resistive element 751 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24.

[0067] Furthermore, one end of the first resistive element 751 is connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22 via vias and wiring layers (not shown) formed on the substrate 15. In addition, as shown in Figure 16, the first resistive element 751 is connected in parallel to the first semiconductor element 21 and the second semiconductor element 22.

[0068] The second resistive element 752 corresponds to a heat-generating component; it is an electrical resistor that generates heat when current flows through it. Furthermore, as shown in Figure 15, the second resistive element 752 is connected to the back surface 152 of the substrate in the thickness direction DT. In addition, one end of the second resistive element 752 is connected to the second P terminal 612 via vias and wiring layers (not shown) formed on the substrate 15. When the second resistive element 752 is projected in the thickness direction DT, the projected second resistive element 752 overlaps with the second P terminal 612. Furthermore, when the second resistive element 752 is projected in the thickness direction DT, the projected second resistive element 752 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24.

[0069] Furthermore, one end of the second resistive element 752 is connected to the drain electrode of the first semiconductor element 21 and the drain electrode of the second semiconductor element 22 via vias and wiring layers (not shown) formed on the substrate 15. In addition, as shown in Figure 16, the second resistive element 752 is connected in parallel to the first semiconductor element 21 and the second semiconductor element 22.

[0070] Furthermore, when the first resistive element 751 is projected in the thickness direction DT, the entire projected portion of the first resistive element 751 overlaps with the first P terminal 611. In addition, when the second resistive element 752 is projected in the thickness direction DT, the entire projected portion of the second resistive element 752 overlaps with the second P terminal 612.

[0071] The first capacitance element 761 is a capacitor and, as shown in Figure 15, is connected to the back surface 152 of the substrate in the thickness direction DT. One end of the first capacitance element 761 is connected to the other end of the resistor element 750 via vias and wiring layers (not shown) formed on the substrate 15. Furthermore, as shown in Figure 16, the first capacitance element 761 is connected in series with the first resistor element 751.

[0072] Furthermore, the other end of the first capacitance element 761 is connected to the source electrode of the third semiconductor element 23 and the source electrode of the fourth semiconductor element 24 via vias and wiring layers (not shown) formed on the substrate 15. In addition, the first capacitance element 761 is connected in parallel to the third semiconductor element 23 and the fourth semiconductor element 24.

[0073] The second capacitance element 762 is a capacitor and, as shown in Figure 15, is connected to the back surface 152 of the substrate in the thickness direction DT. One end of the second capacitance element 762 is connected to the other end of the resistor element 750 via vias and wiring layers (not shown) formed on the substrate 15. Furthermore, as shown in Figure 16, the second capacitance element 762 is connected in series with the second resistor element 752.

[0074] Furthermore, the other end of the second capacitance element 762 is connected to the source electrode of the third semiconductor element 23 and the source electrode of the fourth semiconductor element 24 via vias and wiring layers (not shown) formed on the substrate 15. In addition, the second capacitance element 762 is connected in parallel to the third semiconductor element 23 and the fourth semiconductor element 24.

[0075] Returning to Figure 15, let Sp1 be the area of ​​the surface of the first P terminal 611 facing the first resistive element 751 in the thickness direction DT. Let Sp2 be the area of ​​the surface of the second P terminal 612 facing the second resistive element 752 in the thickness direction DT. Let Sn be the area of ​​the surfaces of the N terminal 63 facing the first capacitive element 761 and the second capacitive element 762 in the thickness direction DT.

[0076] Furthermore, the sum of Sp1 and Sp2 is greater than Sn, i.e., Sp1 + Sp2 > Sn.

[0077] As described above, the semiconductor device 10 of the fourth embodiment is configured. This fourth embodiment also provides the same effects as the first embodiment. Furthermore, the fourth embodiment also provides the effects described below.

[0078] [2-1] The snubber circuit 75 has a first resistive element 751 and a second resistive element 752. When the first resistive element 751 is projected in the thickness direction DT, the projected first resistive element 751 overlaps with the first P terminal 611. When the second resistive element 752 is projected in the thickness direction DT, the projected second resistive element 752 overlaps with the second P terminal 612. The first P terminal 611 corresponds to the first terminal. The second P terminal 612 corresponds to the second terminal.

[0079] This prevents heat from concentrating and being conducted to a single terminal when there are multiple heat-generating components. As a result, the temperature rise of the first P terminal 611 and the second P terminal 612 is suppressed. Therefore, the heat generated in the first resistive element 751 is easily dissipated to the first P terminal 611, and the heat generated in the second resistive element 752 is easily dissipated to the second P terminal 612. Thus, the temperature rise of the first resistive element 751 and the second resistive element 752 is suppressed.

[0080] [2-2] The sum of Sp1 and Sp2 is greater than Sn, i.e., Sp1 + Sp2 > Sn.

[0081] As a result, compared to the case where Sp1 + Sp2 ≤ Sn, the amount of heat transferred from the first resistive element 751 to the first P terminal 611 and from the second resistive element 752 to the second P terminal 612 becomes larger. Therefore, the temperature rise of the first resistive element 751 and the second resistive element 752 is suppressed.

[0082] (Fifth embodiment) In the fifth embodiment, the configurations of terminals P 61 and N 63 differ from those of the first embodiment. Otherwise, it is the same as the first embodiment.

[0083] Here, as shown in Figure 17, Sp0 is the area of ​​the surface of terminal P 61 facing the resistive element 750 in the thickness direction DT. Sn0 is the area of ​​the surface of terminal N 63 facing the capacitive element 760 in the thickness direction DT. Terminal P 61 corresponds to the first terminal, and terminal N 63 corresponds to the second terminal.

[0084] Furthermore, Sp0 is considered to be greater than Sn0, i.e., Sp0 > Sn0.

[0085] Furthermore, when the resistive element 750 is projected in the thickness direction DT, the entire projected resistive element 750 overlaps with terminal P 61.

[0086] As described above, the semiconductor device 10 of the fifth embodiment is configured. This fifth embodiment also provides the same effects as the first embodiment. Furthermore, the fifth embodiment also provides the effects described below.

[0087] [3] Since Sp0 > Sn0, the amount of heat transferred from the resistive element 750 to the P terminal 61 is greater compared to the case where Sp0 ≤ Sn0. Therefore, the temperature rise of the resistive element 750 is suppressed.

[0088] (Sixth Embodiment) In the sixth embodiment, the configuration of the P terminal 61 differs from that of the first embodiment. Otherwise, it is the same as the first embodiment.

[0089] Specifically, as shown in Figure 18, the P terminal 61 has a protrusion 615. The protrusion 615 extends toward the cooler 90 from the portion of the P terminal 61 that overlaps with the resistive element 750. Furthermore, the protrusion 615 is formed in a rectangular prism shape. However, the protrusion 615 is not limited to being formed in a rectangular prism shape, and may be formed in, for example, a cylindrical shape, an arc-shaped prism shape, a hemispherical shape, etc.

[0090] As described above, the semiconductor device 10 of the sixth embodiment is configured. This sixth embodiment also provides the same effects as the first embodiment. Furthermore, the sixth embodiment also provides the effects described below.

[0091] [4] The P terminal 61 has a protrusion 615. The protrusion 615 makes it easier for heat from the P terminal 61 to be transferred to the cooler 90. As a result, the heat generated in the resistive element 750 is easily transferred to the cooler 90 via the P terminal 61. Consequently, the heat generated in the resistive element 750 is easily dissipated, and the temperature rise of the resistive element 750 is suppressed.

[0092] (Seventh Embodiment) In the seventh embodiment, the semiconductor device 10 further includes a connecting member 94 and a heat transfer member 96, as shown in Figure 19. Otherwise, it is the same as in the first embodiment.

[0093] The connecting member 94 is connected to the portion of the P terminal 61 that overlaps with the resistive element 750. The connecting member 94 can be made of, for example, solder, sintered silver, or adhesive.

[0094] The heat transfer member 96 is made of copper or the like. As a result, the thermal conductivity of the heat transfer member 96 is relatively high. Furthermore, the heat transfer member 96 is connected to the connecting member 94 on the side opposite to the P terminal 61. In addition, the heat transfer member 96 protrudes toward the cooler 90 from the boundary with the connecting member 94. Furthermore, the heat transfer member 96 is formed in a rectangular prism shape. However, the heat transfer member 96 is not limited to being formed in a rectangular prism shape, and may be formed in, for example, a cylindrical shape, an arc-shaped prism shape, a hemispherical shape, etc.

[0095] As described above, the semiconductor device 10 of the seventh embodiment is configured as described. This seventh embodiment also provides the same effects as the first embodiment. Furthermore, the seventh embodiment also provides the effects described below.

[0096] [5] The semiconductor device 10 further comprises a connecting member 94 and a heat transfer member 96. This makes it easier for heat from the P terminal 61 to be transferred to the cooler 90. As a result, the heat generated in the resistive element 750 is easily transferred to the cooler 90 via the P terminal 61. Since the heat generated in the resistive element 750 is easily dissipated, the temperature rise of the resistive element 750 is suppressed.

[0097] (Eighth embodiment) In the eighth embodiment, the semiconductor device 10 further includes a connecting member 94, a first heat transfer member 961, an insulating member 98, and a second heat transfer member 962, as shown in Figure 20. Otherwise, it is the same as in the first embodiment.

[0098] The connecting member 94 is connected to the portion of the P terminal 61 that overlaps with the resistive element 750. The connecting member 94 can be made of, for example, solder, sintered silver, or adhesive.

[0099] The first heat transfer member 961 is made of copper or the like. As a result, the thermal conductivity of the first heat transfer member 961 is relatively high. Furthermore, the first heat transfer member 961 is connected to the side of the connecting member 94 opposite to the P terminal 61. The first heat transfer member 961 is also formed in a plate shape. However, the first heat transfer member 961 is not limited to being formed in a plate shape, and may be formed in, for example, a cylindrical shape, an arc-shaped column, a hemispherical shape, etc.

[0100] The insulating member 98 is made of ceramics or the like. As a result, the insulating member 98 has electrical insulating properties. Furthermore, the insulating member 98 is connected to the side of the first heat transfer member 961 opposite to the connecting member 94. The insulating member 98 is also formed in a plate shape. However, the insulating member 98 is not limited to being formed in a plate shape, and may be formed in, for example, a cylindrical shape, an arc-shaped column, a hemispherical shape, etc.

[0101] The second heat transfer member 962 is made of copper or the like. As a result, the thermal conductivity of the second heat transfer member 962 is relatively high. Furthermore, the second heat transfer member 962 is connected to the insulating member 98 on the side opposite to the first heat transfer member 961. The second heat transfer member 962 is also formed in a plate shape. Therefore, the second heat transfer member 962, together with the first heat transfer member 961 and the insulating member 98, constitutes an insulating circuit board. Furthermore, the second heat transfer member 962 faces the cooler 90 in the thickness direction DT. Also, the side of the second heat transfer member 962 opposite to the insulating member 98 is exposed from the sealing resin 80. Furthermore, the side of the second heat transfer member 962 opposite to the insulating member 98 is connected to the heat conduction member 85. Note that the second heat transfer member 962 is not limited to being formed in a plate shape, but may be formed in, for example, a cylindrical shape, an arc-shaped column, a hemispherical shape, etc.

[0102] As described above, the semiconductor device 10 of the eighth embodiment is configured as described. This eighth embodiment also provides the same effects as the first embodiment. Furthermore, the eighth embodiment also provides the effects described below.

[0103] [6] The semiconductor device 10 further comprises a connecting member 94, a first heat transfer member 961, an insulating member 98, and a second heat transfer member 962.

[0104] As a result, heat from terminal P 61 is more easily transferred to the cooler 90. Therefore, the heat generated in the resistor 750 is more easily transferred to the cooler 90 via terminal P 61. Consequently, the heat generated in the resistor 750 is more easily dissipated, and the temperature rise of the resistor 750 is suppressed.

[0105] (Ninth Embodiment) In the ninth embodiment, the semiconductor device 10 further includes a heat transfer member 96 and an insulating member 98, as shown in Figure 21. Otherwise, it is the same as in the first embodiment.

[0106] The heat transfer member 96 is made of copper or the like. As a result, the thermal conductivity of the heat transfer member 96 is relatively high. Furthermore, the heat transfer member 96 is connected to the side of the insulating member 98 (described later) opposite to the P terminal 61. The heat transfer member 96 is also formed in a rectangular prism shape. Furthermore, the heat transfer member 96 faces the cooler 90 in the thickness direction DT. Also, the side of the heat transfer member 96 opposite to the insulating member 98 is exposed from the sealing resin 80. Furthermore, the side of the heat transfer member 96 opposite to the insulating member 98 is connected to the heat conduction member 85. Note that the heat transfer member 96 is not limited to being formed in a plate shape, but may be formed in, for example, a cylindrical shape, an arc-shaped prism shape, a hemispherical shape, etc.

[0107] The insulating member 98 is made of resin, ceramics, or the like. As a result, the insulating member 98 has electrical insulating properties. The insulating member 98 is also connected to the portion of the P terminal 61 that overlaps with the resistive element 750 via an adhesive or the like. Furthermore, the insulating member 98 is formed in a rectangular prism shape. However, the insulating member 98 is not limited to being formed in a rectangular prism shape, and may be formed in, for example, a cylindrical shape, an arc-shaped prism shape, a hemispherical shape, etc.

[0108] As described above, the semiconductor device 10 of the ninth embodiment is configured. This ninth embodiment also provides the same effects as the first embodiment. Furthermore, the ninth embodiment also provides the effects described below.

[0109] [7] The semiconductor device 10 further comprises an insulating member 98 and a heat transfer member 96. This makes it easier for heat from the P terminal 61 to be transferred to the cooler 90. As a result, the heat generated in the resistive element 750 is easily transferred to the cooler 90 via the P terminal 61. Therefore, the heat generated in the resistive element 750 is easily dissipated, and the temperature rise of the resistive element 750 is suppressed.

[0110] (Tenth embodiment) In the tenth embodiment, the form of the heat conductive member 85 differs from that of the first embodiment. Otherwise, it is the same as the first embodiment.

[0111] In the first embodiment, when the heat conductive member 85 is projected in the thickness direction DT, the projected heat conductive member 85 overlaps with the P terminal 61. In contrast, in the tenth embodiment, as shown in Figure 22, when the heat conductive member 85 is projected in the thickness direction DT, the projected heat conductive member 85 does not overlap with the P terminal 61.

[0112] As described above, the semiconductor device 10 of the tenth embodiment is configured as described above. This tenth embodiment is the same as the first embodiment.

[0113] (11th embodiment) In the eleventh embodiment, the semiconductor device 10 includes a first heat conductive member 851 and a second heat conductive member 852 instead of the heat conductive member 85, as shown in Figure 23. Otherwise, it is the same as in the first embodiment.

[0114] The first heat conductive member 851 is formed in a gel, sheet, or clay-like state using epoxy resin or the like for underfill and sidefill. Furthermore, the first heat conductive member 851 is connected in the thickness direction DT to the portion of the sealing resin 80 that overlaps with the P terminal 61 and to the portion of the cooler 90. When the first heat conductive member 851 is projected in the thickness direction DT, the projected first heat conductive member 851 overlaps with the P terminal 61, the resistor element 750, and the cooler 90. Furthermore, when the first heat conductive member 851 is projected in the thickness direction DT, the projected first heat conductive member 851 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24.

[0115] The second heat conductive member 852 is made of a different material from the first heat conductive member 851 and is formed in a gel-like, sheet-like, or clay-like state. For example, the material of the second heat conductive member 852 may be solder or sintered silver. The second heat conductive member 852 is connected to the exposed surface of the second heat dissipation section 514 and the exposed surface of the fourth heat dissipation section 524 in the thickness direction DT. Furthermore, when the second heat conductive member 852 is projected in the thickness direction DT, the projected second heat conductive member 852 overlaps with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24 and the cooler 90. When the second heat conductive member 852 is projected in the thickness direction DT, the projected second heat conductive member 852 does not overlap with the P terminal 61 and the resistive element 750.

[0116] As described above, the semiconductor device 10 of the 11th embodiment is configured. This 11th embodiment also provides the same effects as the first embodiment. Furthermore, the 11th embodiment also provides the effects described below.

[0117] [8] The semiconductor device 10 includes a first heat conductive member 851 and a second heat conductive member 852. The material of the first heat conductive member 851 is different from the material of the second heat conductive member 852. The first heat conductive member 851 contains epoxy resin. This makes the connection with the sealing resin 80 and the cooler 90 relatively strong.

[0118] (12th embodiment) In the twelfth embodiment, the configuration of the P terminal 61 and the first heat dissipation member 51 differs from that of the first embodiment. Otherwise, it is the same as the first embodiment.

[0119] Specifically, as shown in Figure 24, when the resistive element 750 is projected in the thickness direction DT, the projected resistive element 750 does not overlap with the P terminal 61.

[0120] Furthermore, the first heat dissipation portion 510, the first insulating portion 512, and the second heat dissipation portion 514 of the first heat dissipation member 51 extend in a direction perpendicular to the thickness direction DT. As a result, when the resistive element 750 is projected onto the thickness direction DT, the projected resistive element 750 overlaps with the first heat dissipation portion 510, the first insulating portion 512, and the second heat dissipation portion 514.

[0121] As described above, the semiconductor device 10 of the 12th embodiment is configured as described. This 12th embodiment also provides the same effects as the first embodiment.

[0122] (13th Embodiment) In the 13th embodiment, the configuration of the P terminal 61 differs from that of the 12th embodiment. Otherwise, it is the same as the 12th embodiment.

[0123] Specifically, as shown in Figure 25, when the resistive element 750 is projected in the thickness direction DT, the projected resistive element 750 does not overlap with the P terminal 61, but rather overlaps with the P terminal 61.

[0124] As described above, the semiconductor device 10 of the 13th embodiment is configured as described above. This 13th embodiment also provides the same effects as the 12th embodiment.

[0125] (14th Embodiment) In the 14th embodiment, the semiconductor device 10 further includes a connecting member 94. Otherwise, it is the same as in the 13th embodiment.

[0126] The connecting member 94 is formed of solder or the like. Furthermore, as shown in Figure 26, the connecting member 94 is connected to the P terminal 61 on the side opposite to the P terminal bonding material 71 in the thickness direction DT. In addition, the connecting member 94 is connected to the first heat dissipation section 510.

[0127] As described above, the semiconductor device 10 of the 14th embodiment is configured as described above. This 14th embodiment also provides the same effects as the 13th embodiment.

[0128] (15th Embodiment) In the 15th embodiment, the semiconductor device 10 further includes a shunt resistor 100, as shown in Figures 27 and 28. Otherwise, it is the same as in the first embodiment.

[0129] As shown in Figure 27, the shunt resistor 100 is connected to the back surface 152 of the substrate and the thickness direction DT. When the shunt resistor 100 is projected onto the thickness direction DT, the projected shunt resistor 100 overlaps with the O terminal 62, the heat conductive member 85, and the cooler 90.

[0130] Furthermore, the shunt resistor 100 is connected to the source electrode of the first semiconductor element 21 via vias and wiring layers formed on the substrate 15 and the bonding material 31 for the first semiconductor element. Additionally, the shunt resistor 100 is connected to the source electrode of the second semiconductor element 22 via vias and wiring layers formed on the substrate 15 and the bonding material 32 for the second semiconductor element. Furthermore, the shunt resistor 100 is connected to the drain electrode of the third semiconductor element 23 and the drain electrode of the fourth semiconductor element 24 via vias and wiring layers formed on the substrate 15, the bonding material, and the third heat dissipation section 520. Finally, the shunt resistor 100 is connected to the O terminal 62 via vias and wiring layers formed on the substrate 15 and the bonding material 72 for the O terminal. Therefore, as shown in Figure 28, one end of the shunt resistor 100 is connected to the source electrode of the first semiconductor element 21, the source electrode of the second semiconductor element 22, the drain electrode of the third semiconductor element 23, and the drain electrode of the fourth semiconductor element 24. The other end of the shunt resistor 100 is connected to terminal O 62. Therefore, the shunt resistor 100 detects the current flowing to terminal O 62, which corresponds to the on / off states of the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24.

[0131] As described above, the semiconductor device 10 of the 15th embodiment is configured as described. This 15th embodiment also provides the same effects as the first embodiment.

[0132] (16th Embodiment) In the sixteenth embodiment, the configurations of the first resistive element 751 and the second resistive element 752 differ from those of the fourth embodiment. Otherwise, it is the same as the fourth embodiment.

[0133] Specifically, as shown in Figures 29 and 30, the first resistive element 751 is connected to the substrate surface 150 and the thickness direction DT instead of the substrate back surface 152. Furthermore, as shown in Figure 30, the first resistive element 751 is positioned between the first semiconductor element 21 and the first P terminal 611 in a direction perpendicular to the thickness direction DT. Also, when the first resistive element 751 is projected in the thickness direction DT, the projected first resistive element 751 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24 and the first P terminal 611. When the first resistive element 751 is projected in a direction perpendicular to the thickness direction DT, the projected first resistive element 751 overlaps with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24 and the first P terminal 611.

[0134] Here, let Drp1 be the shortest distance from the first resistive element 751 to the first P terminal 611 in the direction perpendicular to the thickness direction DT. Let Drs1 be the shortest distance from the first resistive element 751 to the first semiconductor element 21 in the direction perpendicular to the thickness direction DT.

[0135] And Drp1 is shorter than Drs1, that is, Drp1 <Drs1とされている。

[0136] As shown in Figures 29 and 31, the second resistive element 752 is connected to the substrate surface 150 and the thickness direction DT instead of the substrate back surface 152. Furthermore, as shown in Figure 31, the second resistive element 752 is positioned between the first semiconductor element 21 and the second P terminal 612 in a direction perpendicular to the thickness direction DT. When the second resistive element 752 is projected in the thickness direction DT, the projected second resistive element 752 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24 and the second P terminal 612. When the second resistive element 752 is projected in a direction perpendicular to the thickness direction DT, the projected second resistive element 752 overlaps with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24 and the second P terminal 612.

[0137] Here, as shown in Figure 31, the shortest distance from the second resistive element 752 to the second P terminal 612 in the direction perpendicular to the thickness direction DT is defined as Drp2. The shortest distance from the second resistive element 752 to the first semiconductor element 21 in the direction perpendicular to the thickness direction DT is defined as Drs2.

[0138] And Drp2 is shorter than Drs2, that is, Drp2 <Drs2とされている。

[0139] As described above, the semiconductor device 10 of the 16th embodiment is configured. This 16th embodiment also provides the same effects as the 4th embodiment.

[0140] (17th Embodiment) In the 17th embodiment, the form of the resistive element 750 differs from that of the first embodiment. Otherwise, it is the same as the first embodiment.

[0141] Specifically, as shown in Figures 32 and 33, the resistive element 750 is connected to the substrate surface 150 and the thickness direction DT instead of the substrate back surface 152. Furthermore, the resistive element 750 is positioned between the first semiconductor element 21 and the P terminal 61 in a direction perpendicular to the thickness direction DT. Also, when the resistive element 750 is projected onto the thickness direction DT, the projected resistive element 750 does not overlap with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24 and the P terminal 61. When the resistive element 750 is projected onto a direction perpendicular to the thickness direction DT, the projected resistive element 750 overlaps with the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, the fourth semiconductor element 24 and the P terminal 61.

[0142] Here, Drp0 is defined as the shortest distance from the resistive element 750 to terminal P 61 in the direction perpendicular to the thickness direction DT. Drs0 is defined as the shortest distance from the resistive element 750 to the first semiconductor element 21 in the direction perpendicular to the thickness direction DT.

[0143] And Drp0 is shorter than Drs0, that is, Drp0 <Drs0とされている。

[0144] As described above, the semiconductor device 10 of the 17th embodiment is configured as described. This 17th embodiment also provides the same effects as the first embodiment.

[0145] (Other embodiments) This disclosure is not limited to the embodiments described above, and modifications can be made to these embodiments as appropriate. Furthermore, it goes without saying that, in each of the embodiments described above, the elements constituting the embodiment are not necessarily essential, except in cases where they are explicitly stated to be particularly essential or where they are clearly considered essential in principle.

[0146] In each of the above embodiments, the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24 are MOSFETs. However, the first semiconductor element 21, the second semiconductor element 22, the third semiconductor element 23, and the fourth semiconductor element 24 are not limited to being MOSFETs, and may be, for example, IGBTs. IGBT stands for Insulated Gate Bipolar Transistor.

[0147] In each of the above embodiments, the P terminal 61, O terminal 62, N terminal 63, first P terminal 611, and second P terminal 612 are formed in a plate shape. In contrast, the P terminal 61, O terminal 62, N terminal 63, first P terminal 611, and second P terminal 612 are not limited to being formed in a plate shape, but may be formed in a rod shape such as a cylindrical shape or an arc-shaped cylindrical shape.

[0148] In each of the above embodiments, the heat-generating components are the resistor element 750, the first resistor element 751, and the second resistor element 752 of the snubber circuit 75. However, the heat-generating components are not limited to the first resistor element 751 and the second resistor element 752 of the snubber circuit 75, and may be, for example, the shunt resistor 100.

[0149] In each of the above embodiments, the first heat dissipation member 51 and the second heat dissipation member 52 are insulating circuit boards. However, the first heat dissipation member 51 and the second heat dissipation member 52 are not limited to insulating circuit boards, and may be, for example, copper plates.

[0150] In each of the embodiments described above, the back surface 152 of the substrate is exposed from the sealing resin 80. However, the back surface 152 of the substrate is not limited to being exposed from the sealing resin 80. The back surface 152 of the substrate may not be exposed from the sealing resin 80, but may be covered by the sealing resin 80.

[0151] In each of the above embodiments, the second heat dissipation section 514 and the fourth heat dissipation section 524 are exposed from the sealing resin 80. However, the second heat dissipation section 514 and the fourth heat dissipation section 524 are not limited to being exposed from the sealing resin 80. The second heat dissipation section 514 and the fourth heat dissipation section 524 may not be exposed from the sealing resin 80 and may be covered by the sealing resin 80.

[0152] In the eighth embodiment described above, the second heat transfer member 962 is exposed from the sealing resin 80. However, the second heat transfer member 962 is not limited to being exposed from the sealing resin 80. The second heat transfer member 962 may not be exposed from the sealing resin 80, but may be covered by the sealing resin 80.

[0153] In the ninth embodiment described above, the heat transfer member 96 is exposed from the sealing resin 80. However, the heat transfer member 96 is not limited to being exposed from the sealing resin 80. The heat transfer member 96 may not be exposed from the sealing resin 80, but may be covered by the sealing resin 80.

[0154] The above embodiments may be combined as appropriate.

[0155] (Perspective of this disclosure) [Perspective 1] A semiconductor device, Circuit board (15) and The semiconductor elements (21, 22, 23, 24) connected to the surface (150) of the substrate, The substrate is connected to conductive terminals (61, 611, 612), The aforementioned circuit board is connected to a heat-generating component (750, 751, 752) that generates heat when current flows through it, Equipped with, A semiconductor device in which, when the heat-generating component is projected in the thickness direction (DT) of the substrate, the projected heat-generating component overlaps with the terminal. [Perspective 2] The semiconductor device according to viewpoint 1, wherein when the heat-generating component is projected in the thickness direction, the projected heat-generating component does not overlap with the semiconductor element. [Perspective 3] The semiconductor device according to viewpoint 1 or 2, wherein the terminal protrudes from the outside of the semiconductor device and is configured to be connectable to a capacitor (92) that supplies power to the semiconductor device. [Perspective 4] The aforementioned terminal is connected to the back surface (152) of the circuit board. The semiconductor device according to any one of views 1 to 3, wherein the heat-generating component is connected to the surface. [Perspective 5] The terminal is connected to the surface, The semiconductor device according to any one of viewpoints 1 to 3, wherein the heat-generating component is connected to the back surface (152) of the substrate. [Perspective 6] The semiconductor device further comprises a cooler (90), The cooler is positioned on the surface side and cools the terminals, The semiconductor device according to viewpoint 5, wherein when the cooler is projected in the thickness direction, the projected cooler overlaps with the terminal and the heat-generating component. [perspective 7] The terminal has a protrusion (615), The semiconductor device according to viewpoint 6, wherein the protrusion is projected toward the cooler from the portion of the terminal that overlaps with the heat-generating component. [Perspective 8] The semiconductor device further comprises a connecting member (94) and a heat transfer member (96), The connecting member is connected to the portion of the terminal that overlaps with the heat-generating component. The semiconductor device according to viewpoint 6, wherein the heat transfer member is connected to the side of the connecting member opposite to the terminal, and protrudes from the connecting member toward the cooler. [Perspective 9] The semiconductor device further comprises a connecting member (94), a first heat transfer member (961), an insulating member (98), and a second heat transfer member (962). The connecting member is connected to the portion of the terminal that overlaps with the heat-generating component. The first heat transfer member is connected to the connecting member on the side opposite to the terminal, The insulating member has electrical insulating properties and is connected to the first heat transfer member on the side opposite to the connecting member. The semiconductor device according to viewpoint 6, wherein the second heat transfer member is connected to the insulating member on the side opposite to the first heat transfer member and faces the cooler in the thickness direction. [Perspective 10] The semiconductor device further comprises an insulating member (98) and a heat transfer member (96), The insulating member has electrical insulating properties and is connected to the portion of the terminal that overlaps with the heat-generating component. The semiconductor device according to viewpoint 6, wherein the heat transfer member is connected to the insulating member on the side opposite to the terminal and faces the cooler in the thickness direction. [Perspective 11] The semiconductor device further comprises a covering portion (80) and a heat conductive member (85), The covering portion covers the substrate, the semiconductor element, and the terminal. The heat conductive member is connected to the covering portion and the cooler, A semiconductor device according to any one of viewpoints 6 to 10, wherein when the terminal is projected in the thickness direction, the projected terminal overlaps with the heat conductive member. [Perspective 12] The heat conductive member is a first heat conductive member, The semiconductor device further comprises heat dissipation members (51, 52) and a second heat conduction member (852), The heat dissipation member is connected to the semiconductor element on the side opposite to the substrate and is covered by the covering portion. The second heat conductive member is connected to the heat dissipation member and the cooler, When the second heat conductive member is projected in the thickness direction, the projected second heat conductive member overlaps with the semiconductor element. The semiconductor device according to viewpoint 11, wherein the material of the first heat conductive member is different from the material of the second heat conductive member. [Perspective 13] The semiconductor device according to viewpoint 12, wherein the first heat conductive member includes an epoxy resin. [Perspective 14] The semiconductor device includes a snubber circuit (75), The snubber circuit has a resistive element (750) and a capacitive element (760), The heat-generating component is the resistive element, A semiconductor device according to any one of viewpoints 1 to 13, wherein when the resistive element is projected in the thickness direction, the entire projected resistive element overlaps with the terminal. [Perspective 15] The aforementioned terminal is the first terminal (611), The semiconductor device further comprises a second terminal (612) and a snubber circuit (75). The second terminal is connected via the substrate to the same portion of the semiconductor element that is connected to the first terminal, and is conductive. The snubber circuit comprises a first resistive element (751), a second resistive element (752), and capacitive elements (761, 762). The heat-generating component is the first resistive element and the second resistive element, When the first resistive element is projected in the thickness direction, the projected first resistive element overlaps with the first terminal. A semiconductor device according to any one of viewpoints 1 to 13, wherein when the second resistive element is projected in the thickness direction, the projected second resistive element overlaps with the second terminal. [Perspective 16] The aforementioned terminal is the first terminal (61), The semiconductor device further comprises a second terminal (63) and a snubber circuit (75). The second terminal is connected via the substrate to the same portion of the semiconductor element that is connected to the first terminal, and is conductive. The snubber circuit has a resistive element (750) and a capacitive element (760), The heat-generating component is the resistive element, When the resistive element is projected in the thickness direction, the projected resistive element overlaps with the first terminal. When the capacitance element is projected in the thickness direction, the projected capacitance element overlaps with the second terminal. The semiconductor device according to any one of viewpoints 1 to 13, wherein the area (Sp0) of the surface of the first terminal facing the resistive element in the thickness direction is larger than the area (Sn0) of the surface of the second terminal facing the capacitive element in the thickness direction. [Perspective 17] A semiconductor device, Circuit board (15) and The semiconductor elements (21, 22, 23, 24) connected to the surface (150) of the substrate, A heat dissipation member (51) is connected to the semiconductor element on the side opposite to the substrate and extends in a direction perpendicular to the thickness direction (DT) of the substrate, A heat-generating component (750) is connected to the back surface (152) of the aforementioned substrate and generates heat when current flows through it, Equipped with, A semiconductor device in which, when the heat-generating component is projected in the thickness direction, the projected heat-generating component overlaps with the heat-dissipating member. [Perspective 18] The semiconductor device further comprises terminal (61), The terminal is connected to the surface and is conductive. The semiconductor device according to viewpoint 17, wherein when the heat-generating component is projected in the thickness direction, the projected heat-generating component overlaps with the heat dissipation member and the terminal. [Perspective 19] The semiconductor device further comprises a connecting member (94), The semiconductor device according to viewpoint 18, wherein the connecting member is connected to the heat dissipation member and the terminal. [perspective 20] The semiconductor device according to viewpoint 18 or 19, wherein the terminal protrudes from the outside of the semiconductor device and is configured to be connectable to a capacitor (92) that supplies power to the semiconductor device. [Perspective 21] A semiconductor device according to any one of viewpoints 17 to 20, wherein when the heat-generating component is projected in the thickness direction, the projected heat-generating component does not overlap with the semiconductor element. [Perspective 22] A semiconductor device, Circuit board (15) and The semiconductor elements (21, 22, 23, 24) connected to the surface (150) of the substrate, Terminals (61, 611, 612) connected to the aforementioned surface and having conductivity, The aforementioned surface is connected to a heat-generating component (750, 751, 752) that generates heat when an electric current flows through it, Equipped with, A semiconductor device in which the distance from the heat-generating component to the terminal (Drp0, Drp1, Drp2) in a direction perpendicular to the thickness direction (DT) of the substrate is shorter than the distance from the heat-generating component to the semiconductor element (Drs0, Drs1, Drs2) in a direction perpendicular to the thickness direction. [Explanation of Symbols]

[0156] 10 Semiconductor Devices 15 circuit boards 150 substrate surface 21 First Semiconductor Element 22 Second semiconductor element 23 Third Semiconductor Device 24 Fourth Semiconductor Element 61 P terminal 75 Snubber Circuit 750 Resistor element

Claims

1. A semiconductor device, Circuit board (15) and The semiconductor elements (21, 22, 23, 24) are connected to the surface (150) of the substrate, The substrate is connected to conductive terminals (61, 611, 612), The aforementioned substrate is connected to a heat-generating component (750, 751, 752) that generates heat when current flows through it, Equipped with, A semiconductor device in which, when the heat-generating component is projected in the thickness direction (DT) of the substrate, the projected heat-generating component overlaps with the terminal.

2. The semiconductor device according to claim 1, wherein when the heat-generating component is projected in the thickness direction, the projected heat-generating component does not overlap with the semiconductor element.

3. The semiconductor device according to claim 1, wherein the terminal protrudes from the outside of the semiconductor device and is configured to be connectable to a capacitor (92) that supplies power to the semiconductor device.

4. The aforementioned terminal is connected to the back surface (152) of the circuit board. The semiconductor device according to claim 1, wherein the heat-generating component is connected to the surface.

5. The terminal is connected to the surface, The semiconductor device according to claim 1, wherein the heat-generating component is connected to the back surface (152) of the substrate.

6. The semiconductor device further comprises a cooler (90), The cooler is positioned on the surface side and cools the terminals, The semiconductor device according to claim 5, wherein when the cooler is projected in the thickness direction, the projected cooler overlaps with the terminal and the heat-generating component.

7. The terminal has a protrusion (615), The semiconductor device according to claim 6, wherein the protrusion is projected toward the cooler from the portion of the terminal that overlaps with the heat-generating component.

8. The semiconductor device further comprises a connecting member (94) and a heat transfer member (96), The connecting member is connected to the portion of the terminal that overlaps with the heat-generating component. The semiconductor device according to claim 6, wherein the heat transfer member is connected to the connecting member on the side opposite to the terminal and protrudes from the connecting member toward the cooler.

9. The semiconductor device further comprises a connecting member (94), a first heat transfer member (961), an insulating member (98), and a second heat transfer member (962). The connecting member is connected to the portion of the terminal that overlaps with the heat-generating component. The first heat transfer member is connected to the connecting member on the side opposite to the terminal, The insulating member has electrical insulating properties and is connected to the first heat transfer member on the side opposite to the connecting member. The semiconductor device according to claim 6, wherein the second heat transfer member is connected to the insulating member on the side opposite to the first heat transfer member and faces the cooler in the thickness direction.

10. The semiconductor device further comprises an insulating member (98) and a heat transfer member (96), The insulating member has electrical insulating properties and is connected to the portion of the terminal that overlaps with the heat-generating component. The semiconductor device according to claim 6, wherein the heat transfer member is connected to the insulating member on the side opposite to the terminal and faces the cooler in the thickness direction.

11. The semiconductor device further comprises a covering portion (80) and a heat conductive member (85), The covering portion covers the substrate, the semiconductor element, and the terminal. The heat conductive member is connected to the covering portion and the cooler, The semiconductor device according to claim 1, wherein when the terminal is projected in the thickness direction, the projected terminal overlaps with the heat conductive member.

12. The heat conductive member is a first heat conductive member, The semiconductor device further comprises heat dissipation members (51, 52) and a second heat conduction member (852), The heat dissipation member is connected to the semiconductor element on the side opposite to the substrate and is covered by the covering portion. The second heat conductive member is connected to the heat dissipation member and the cooler, When the second heat conductive member is projected in the thickness direction, the projected second heat conductive member overlaps with the semiconductor element. The semiconductor device according to claim 11, wherein the material of the first heat conductive member is different from the material of the second heat conductive member.

13. The semiconductor device according to claim 12, wherein the first heat conductive member comprises an epoxy resin.

14. The semiconductor device includes a snubber circuit (75), The snubber circuit comprises a resistive element (750) and a capacitive element (760). The heat-generating component is the resistive element, The semiconductor device according to any one of claims 1 to 13, wherein when the resistive element is projected in the thickness direction, the entire projected resistive element overlaps with the terminal.

15. The aforementioned terminal is the first terminal (611), The semiconductor device further comprises a second terminal (612) and a snubber circuit (75). The second terminal is connected via the substrate to the same portion of the semiconductor element that is connected to the first terminal, and is conductive. The snubber circuit comprises a first resistive element (751), a second resistive element (752), and capacitive elements (761, 762). The heat-generating component is the first resistive element and the second resistive element, When the first resistive element is projected in the thickness direction, the projected first resistive element overlaps with the first terminal. The semiconductor device according to any one of claims 1 to 13, wherein when the second resistive element is projected in the thickness direction, the projected second resistive element overlaps with the second terminal.

16. The aforementioned terminal is the first terminal (61), The semiconductor device further comprises a second terminal (63) and a snubber circuit (75). The second terminal is connected via the substrate to the same portion of the semiconductor element that is connected to the first terminal, and is conductive. The snubber circuit comprises a resistive element (750) and a capacitive element (760). The heat-generating component is the resistive element, When the resistive element is projected in the thickness direction, the projected resistive element overlaps with the first terminal. When the capacitance element is projected in the thickness direction, the projected capacitance element overlaps with the second terminal. The semiconductor device according to any one of claims 1 to 13, wherein the area of ​​the surface of the first terminal facing the resistive element in the thickness direction (Sp0) is larger than the area of ​​the surface of the second terminal facing the capacitive element in the thickness direction (Sn0).

17. A semiconductor device, Circuit board (15) and The semiconductor elements (21, 22, 23, 24) are connected to the surface (150) of the substrate, A heat dissipation member (51) is connected to the semiconductor element on the side opposite to the substrate and extends in a direction perpendicular to the thickness direction (DT) of the substrate, A heat-generating component (750) is connected to the back surface (152) of the aforementioned substrate and generates heat when current flows through it, Equipped with, A semiconductor device in which, when the heat-generating component is projected in the thickness direction, the projected heat-generating component overlaps with the heat-dissipating member.

18. The semiconductor device further comprises terminals (61), The terminal is connected to the surface and is conductive. The semiconductor device according to claim 17, wherein when the heat-generating component is projected in the thickness direction, the projected heat-generating component overlaps with the heat dissipation member and the terminal.

19. The semiconductor device further comprises a connecting member (94), The semiconductor device according to claim 18, wherein the connecting member is connected to the heat dissipation member and the terminal.

20. The semiconductor device according to claim 18, wherein the terminal protrudes from the outside of the semiconductor device and is configured to be connectable to a capacitor (92) that supplies power to the semiconductor device.

21. The semiconductor device according to any one of claims 17 to 20, wherein when the heat-generating component is projected in the thickness direction, the projected heat-generating component does not overlap with the semiconductor element.

22. A semiconductor device, Circuit board (15) and The semiconductor elements (21, 22, 23, 24) are connected to the surface (150) of the substrate, Terminals (61, 611, 612) connected to the aforementioned surface and having conductivity, The aforementioned surface is connected to a heat-generating component (750, 751, 752) that generates heat when an electric current flows through it, Equipped with, A semiconductor device in which the distance from the heat-generating component to the terminal (Drp0, Drp1, Drp2) in a direction perpendicular to the thickness direction (DT) of the substrate is shorter than the distance from the heat-generating component to the semiconductor element (Drs0, Drs1, Drs2) in a direction perpendicular to the thickness direction.

Images