Semiconductor module
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- DENSO CORP
- Filing Date
- 2022-03-03
- Publication Date
- 2026-07-16
AI Technical Summary
Dissipating heat generated by semiconductor elements in semiconductor modules is challenging, leading to excessive temperature increases.
A semiconductor module design incorporating a substrate, semiconductor elements, and a heat sink plate with a sealed fluid inside, enhancing thermal conductivity and anisotropy to distribute heat effectively and reduce impedance in current paths.
The design effectively suppresses temperature rises in semiconductor elements by improving heat distribution and reducing impedance, enhancing cooling efficiency and thermal conductivity.
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Abstract
Description
[0001] The present invention relates to a semiconductor module.
[0002] US 10,229,895 B2 discloses a semiconductor module. This semiconductor module comprises a substrate and a semiconductor element located within the substrate. The semiconductor element is a power element and generates a large amount of heat along with electrical conductivity.
[0003] In the structure in which the semiconductor element, in particular the energy semiconductor element, is arranged on the substrate of a semiconductor device in such a semiconductor module as described in US 10 229 895 B2, it may be difficult to dissipate the heat generated by the semiconductor element to the outside, so that an excessive increase in the temperature of the semiconductor element may occur.
[0004] The object of the present invention is to provide a semiconductor module with a built-in semiconductor element in a circuit board in order to suppress an increase in the temperature of the semiconductor element.
[0005] According to one aspect of the present invention, a semiconductor module comprises a substrate, a semiconductor element, and a heat sink plate. The substrate is contained within a printed circuit board. The semiconductor element is arranged on the heat sink plate inside the substrate. A fluid is sealed inside the heat sink plate.
[0006] By employing a structure in which the fluid is sealed, for example, inside the heat sink plate, it is possible to improve the thermal conductivity of the heat sink plate and provide anisotropy for heat conduction across the plate. As a result, the heat generated by the semiconductor element can be distributed over a larger area of the substrate via the heat sink plate, and a rise in the semiconductor element's temperature can be effectively suppressed.
[0007] Other features, characteristics and advantages of the present invention are illustrated by the following detailed description, which is made with reference to the accompanying figures. These show: Fig. 1 a top view of a semiconductor module according to one embodiment; Fig. 2 a cross-sectional view along line II-II in Fig. 1 is recorded; Fig. 3 a circuit diagram illustrating the circuit configuration of the semiconductor module according to the embodiment; Fig. 4 a perspective view of a heat sink plate; Fig. 5A a top view of the heat sink plate; Fig. 5B a cross-sectional view of the heat sink plate, which runs along the line VB-VB in Fig. 5A is recorded; Fig. 6A a top view of a heat sink plate according to a first modification; Fig. 6B a cross-sectional view of the heat sink plate, which runs along the line VIB-VIB in Fig. 6A is recorded; Fig. 7A a top view of the heat sink plate according to a second modification; Fig. 7B a cross-sectional view of the heat sink plate, which runs along line VIIB-VIIB in Fig. 7A is recorded; and Fig. 8 is an example where several semiconductor elements are arranged on a single heat sink plate.
[0008] In a semiconductor module according to the present embodiment, the thermal conductivity of a heat sink plate can exhibit anisotropy in a top view. According to such a structure, it is possible to effectively distribute the heat generated by a semiconductor element according to the shape of the heat sink plate or the shape of a substrate.
[0009] In the present embodiment, the heat sink plate can have a rectangular outer shape. In this situation, the thermal conductivity in the longitudinal direction of the heat sink plate can be higher than the thermal conductivity in the lateral direction of the heat sink plate. According to such a structure, it is possible to distribute the heat generated by the semiconductor element uniformly over the entire heat sink plate.
[0010] In the present embodiment, it is further possible to provide multiple terminals exposed on the substrate surface and electrically connected to the semiconductor element. In this configuration, the multiple terminals can be arranged oriented laterally towards the heat sink plate. With such a structure, it is possible to shorten the current path connecting the multiple terminals and the semiconductor element, thereby reducing the impedance of the current path. A reduced impedance suppresses heat generation in the current path, thus also suppressing the temperature rise in the semiconductor element.
[0011] In the following embodiment of the present description, the heat sink plate can be a heat tube or a steam chamber. The heat tube and the steam chamber are examples of the heat transfer element in which the fluid is enclosed, and such a heat transfer element can be used appropriately as the heat sink plate described in the present description.
[0012] In the present embodiment, the heat sink plate can be made of metal or graphite. Both metal and graphite are materials that exhibit excellent thermal conductivity, and such heat transfer elements can be appropriately used for the heat sink plate described in this description.
[0013] In the present embodiment described above, a semiconductor module can further comprise a control unit that regulates the operation of the semiconductor element. According to such a structure, it is possible to suppress the temperature rise in the semiconductor element. Consequently, it is possible to avoid a situation in which the control unit overheats when the control unit is located on the substrate surface.
[0014] According to another aspect of the present description, it is possible to reduce the impedance of the current path in the semiconductor module, which incorporates a built-in semiconductor element. In the following embodiment of the present description, the semiconductor module can comprise a substrate, a semiconductor element, a heat sink plate, and multiple terminals. The semiconductor element is arranged within the substrate. The heat sink plate is provided with the semiconductor element inside the substrate. The multiple terminals are exposed on the surface of the substrate and electrically connected to the semiconductor element inside the substrate.
[0015] In the present embodiment of this description, the heat sink plate can have a rectangular outer shape. In this configuration, the multiple terminals can be arranged laterally along the heat sink plate. With such a structure, it is possible to shorten the current path connecting the multiple terminals and the semiconductor element, thereby reducing the current path impedance.
[0016] In the following embodiment, at least one of the multiple terminals is located on one side of the heat sink plate to be oriented laterally towards the heat sink plate, and at least one other of the multiple terminals is located on the other side of the heat sink plate to be oriented laterally towards the heat sink plate. According to such a structure, it is possible to effectively shorten the current path connecting the multiple terminals and the semiconductor element, thereby further reducing the impedance of the current path. (Form of execution)
[0017] A semiconductor module 10 according to the embodiment is described below with reference to the figures. The semiconductor module 10 according to the present embodiment is used, for example, in an energy control unit or power control unit in an electric vehicle and can convert energy between a power supply and a drive motor. In the present embodiment, the term "electric vehicle" broadly refers to a vehicle that has a motor for driving wheels and is, for example, an electric vehicle that is charged by external electrical energy, a hybrid vehicle that has an internal combustion engine in addition to the motor, a fuel cell vehicle that has a fuel cell as an energy source, and the like. However, the application of the semiconductor module 10 according to the present embodiment is not limited to electric vehicles and can be used for a variety of electrical devices.
[0018] As in the Fig. 1 to Fig. As shown in Figure 3, the semiconductor module 10 comprises a substrate 12, several semiconductor elements 21 to 26, and several heat sink plates 31 to 36. The substrate 12 can also be referred to as the substrate body or substrate core. The substrate 12 has a board-like or plate-like shape. The substrate 12 has a top surface 12a and a bottom surface 12b. The bottom surface 12b is located on a side opposite the top surface 12a. The substrate 12 is made of an insulator, for example, an epoxy resin or another resin material.
[0019] In the figures, the X-direction and the Y-direction are directions parallel to the upper surface 12a and the lower surface 12b of the substrate 12, respectively, and perpendicular to each other. The Z-direction is a direction perpendicular to the upper surface 12a and the lower surface 12b of the substrate 12, and perpendicular to both the X-direction and the Y-direction.
[0020] The semiconductor elements 21 to 26 are arranged inside the substrate 12 and are sealed by the substrate 12. Each of the semiconductor elements 21 and 22 is a power semiconductor element, in particular a switching element. This switching element can be, for example, an insulated gate bipolar transistor (IGBT) or a metal-oxide-semiconductor field-effect transistor (MOSFET). The semiconductor elements 21 to 26 each have upper surface electrodes 21a to 26a and lower surface electrodes 21b to 26b and conduct electricity or block electrical conductivity between the corresponding upper surface electrodes 21a to 26a and the corresponding lower surface electrodes 21b to 26b.
[0021] For example, in the semiconductor module 10 in the present embodiment, the multiple semiconductor elements 21 to 26 are each designated as a first semiconductor element 21, a second semiconductor element 22, a third semiconductor element 23, a fourth semiconductor element 24, a fifth semiconductor element 25, and a sixth semiconductor element 26. The first semiconductor element 21 and the second semiconductor element 22 are electrically connected in series inside the substrate 12. The third semiconductor element 23 and the fourth semiconductor element 24 are electrically connected in series inside the substrate 12. The fifth semiconductor element 25 and the sixth semiconductor element 26 are electrically connected in series inside the substrate 12.
[0022] The heat sink plates 31 to 36 are arranged inside the substrate 12 and are sealed by the substrate 12. Each of the heat sink plates 31 to 36 has a board-like or plate-like shape and is arranged in the same plane parallel to the substrate 12. In other words, each of the heat sink plates 31 to 36 is perpendicular to the Z-direction. Each of the heat sink plates 31 to 36 has a conductor such as copper, a metal other than copper, or graphite. The structure of each of the heat sink plates 31 to 36 is described below.
[0023] As an example, the heat sink plates 31 to 36 in the semiconductor module 10 according to the present embodiment are each designated as a first heat sink plate 31, a second heat sink plate 32, a third heat sink plate 33, a fourth heat sink plate 34, a fifth heat sink plate 36, and a sixth heat sink plate 36. The first heat sink plate 31 and the second heat sink plate 32 are oriented in the X direction. The third heat sink plate 33 and the fourth heat sink plate 34 are oriented in the X direction. The fifth heat sink plate 35 and the sixth heat sink plate 36 are oriented in the X direction. The first heat sink plate 31, the third heat sink plate 33, and the fifth heat sink plate 35 are oriented in the Y direction. The second heat sink plate 32, the fourth heat sink plate 34 and the sixth heat sink plate 36 are aligned in the Y direction.
[0024] The first semiconductor element 21 is arranged on the first heat sink plate 31, and the lower surface electrode 21b of the first semiconductor element 21 is electrically connected to the first heat sink plate 31. The second semiconductor element 22 to the sixth semiconductor element 26 are each arranged on the second heat sink plate 32 to the sixth heat sink plate 36. The lower surface electrodes 22b to 26b present in the second semiconductor element 22 and the sixth semiconductor element 26, respectively, are electrically connected to the second heat sink plate 32 and the sixth heat sink plate 36.
[0025] The semiconductor module 10 has terminals 40, 42, 44, 46, and 48. These terminals 40, 42, 44, 46, and 48 are external connection terminals for connecting to an external circuit. The terminals 40, 42, 44, 46, and 48 are made of a conductor, such as copper or another material. For example, the terminals 40, 42, 44, 46, and 48 are designated as P-terminal 40, N-terminal 42, U-terminal 44, V-terminal 46, and W-terminal 48, respectively. The P-terminal 40 and the N-terminal 42 are arranged such that they each face one side of the heat sink plates 31 to 36 in the X direction. The U-connection 44, the V-connection 46, and the W-connection 48 are arranged such that they each point towards the opposite side of the heat sink plates 31 to 36 in the X direction. The connections 40, 42, 44, 46, and 48 are located on the lower surface 12b of the substrate 12.However, one or more of the connections 40, 42, 44, 46, 48 can be located on the upper surface 12a of the substrate 12.
[0026] The P-terminal 40 is electrically connected to the first heat sink plate 31, the third heat sink plate 33, and the fifth heat sink plate 35 inside the substrate 12. As a result, the P-terminal 40 is electrically connected via one of the heat sink plates 31, 33, 35 to the respective lower surface electrodes 21b, 23b, 25b of the first semiconductor element 21, the third semiconductor element 23, and the fifth semiconductor element 25, respectively. The N-terminal 42 is electrically connected to the respective upper surface electrodes 22a, 24a, 26a of the second semiconductor element 22, the fourth semiconductor element 24, and the sixth semiconductor element 26 inside the substrate 12.
[0027] The U-terminal 44 is electrically connected to the upper surface electrode 21a of the first semiconductor element 21 inside the substrate 12. The U-terminal 44 is electrically connected to the second heat sink plate 32 and, via the second heat sink plate 32, to the lower surface electrode 22b of the second semiconductor element 22. The V-terminal 46 is electrically connected to the upper surface electrode 23a of the third semiconductor element 23 and the fourth heat sink plate 34, and, via the fourth heat sink plate 34, to the lower surface electrode 24b of the fourth semiconductor element 24. The W-terminal 48 is electrically connected to the upper surface electrode 25a of the fifth semiconductor element 25 and the sixth heat sink plate 36, and, via the sixth heat sink plate 36, to the lower surface electrode 26b of the sixth semiconductor element 26.
[0028] The semiconductor module 10 in the present embodiment is arranged between a direct current (DC) circuit and a three-phase alternating current (AC) circuit and can function as a three-phase inverter circuit. In this configuration, the P terminal 40 and the N terminal 42 are connected to the DC circuit, and the U terminal 44, the V terminal 46, and the W terminal 48 are connected to the three-phase AC circuit. Since the semiconductor elements 21 to 26 are selectively switched on and off, each of the terminals, U terminal 44, V terminal 46, and W terminal 48, is electrically connected to either the P terminal 40 or the N terminal 42.As a result, the semiconductor module 10 converts DC energy from the DC circuit into AC energy and supplies the AC energy to the three-phase AC circuit, or converts the AC energy from the three-phase AC circuit into DC energy and supplies the DC energy to the DC circuit. As described above, the semiconductor module 10 in the present embodiment can, for example, be used in an electric vehicle. In this situation, the semiconductor module 10 is arranged between a power supply device (a DC circuit) and the drive motor (a three-phase AC circuit) and performs an energy conversion between the power supply device and the drive motor.
[0029] The semiconductor module 10 further comprises a control circuit 50. The control circuit 50 is arranged on the upper surface 12a of the substrate 12. The control circuit 50 comprises several planar electrical components 52. The planar electrical components 52 include, for example, a gate drive circuit that controls the switching of the semiconductor elements 21 to 26. As described above, in the present embodiment, the semiconductor module 10 has a structure in which the semiconductor elements 21 to 26 and the heat sink plates 31 to 36 are integrated into a printed circuit board that includes the control circuit 50. The number of semiconductor elements 21 to 26 and the number of heat sink plates 31 to 36 are not particularly limited. The semiconductor module 10 can have at least one semiconductor element and at least one heat sink plate.In this case, the semiconductor element is not limited to the switching element and can also be another type of semiconductor element, such as a diode.
[0030] The following section describes the heat sink plates 31 to 36 with reference to the Fig. 4, Fig. 5A, Fig. 5B described. In the present embodiment, the heat sink plates 31 to 36 each have identical structures. Consequently, in the Fig. 4, Fig. 5A and Fig. Figure 5B shows only the first heat sink plate 31, and the representation of the other heat sink plates 32 to 36 is omitted. However, some or all of the heat sink plates 31 to 36 may have different structures.
[0031] As in Fig. As shown in Figure 4, the heat sink plates 31 to 36 each have a rectangular outer shape. The longitudinal direction of each of the heat sink plates 31 to 36 is parallel to the Y-direction, and the lateral direction of each of the heat sink plates 31 to 36 is parallel to the X-direction. In the semiconductor module according to the present embodiment, the terminals 40, 42, 44, 46, 48 are arranged such that they are directed towards the heat sink plates 31 to 36 in the X-direction. In other words, the terminals 40, 42, 44, 46, 48 are arranged such that they are directed towards the heat sink plates 31 to 36 in the lateral direction. According to such a structure it is possible to increase the size of each of the heat sink plates 31 to 36, while shortening the distance between each of the connections 40, 42, 44, 46, 48 and each of the heat sink plates 31 to 36.
[0032] Increasing the size of each of the heat sink plates 31 to 36 distributes the heat generated by the semiconductor elements 21 to 26 over a wider area of the substrate 12. As a result, the temperature rise in the semiconductor elements 21 to 26 is effectively suppressed. Reducing the distance between each of the terminals 40, 42, 44, 46, 48 and each of the heat sink plates 31 to 36 shortens the current path through which the current flows in the substrate 12 and reduces the impedance in the current path. Enlarging each of the heat sink plates 31 to 36 so that they have a rectangular shape in one direction and arranging the terminals 40, 42, 44, 46, 48 in the lateral direction of this rectangular shape further improves cooling performance and reduces impedance.
[0033] As in Fig. Figure 5B shows a cross-sectional view of the heat sink plate 31, which runs along the line VB-VB in Fig. 5A is recorded, several spaces 31a are formed inside the heat sink 31, and a fluid 38 is inside each of the spaces 31a in a cross-sectional view of the heat sink plate 31, which is along the line VB-VB in Fig. 5A is sealed. The fluid 38 is heated and evaporates in a high-temperature section of each of the heat sink plates 31 to 36. The fluid 38 condenses and liquefies in a low-temperature section of each of the heat sink plates 31 to 36. By repeating the cycle described above, convection of the fluid 38 is generated in space 31a, and the heat conduction in each of the heat sink plates 31 to 36 is improved. As a result, the heat generated in each of the semiconductor elements 21 to 26 is distributed over a larger area in the substrate 12, and the temperature rise in each of the semiconductor elements 21 to 26 is effectively suppressed.
[0034] Although not particularly limited, each of the heat sink plates 31 to 36 in the present embodiment has a so-called heat tube structure. Each of the spaces 31a inside the heat sink plates 31 to 36 extends in a tubular shape, and the fluid 38 in each of the spaces 31a convects along a longitudinal direction of the tubular shape. In other words, the fluid 38 convects along the longitudinal direction (Y-direction) of each of the heat sink plates 31 to 36. Each of the spaces 31a, which have a tubular shape, extends along the longitudinal direction of each of the heat sink plates 31 to 36. Consequently, the thermal conductivity of each of the heat sink plates 31 to 36 exhibits anisotropy in plan view. The thermal conductivity in the longitudinal direction or a longer side of each of the heat sink plates 31 to 36 is higher than the thermal conductivity in the lateral direction or a shorter side of each of the heat sink plates 31 to 36.According to such a structure, it is possible in each of the rectangular heat sink plates 31 to 36 to distribute the heat generated by each of the semiconductor elements 21 to 26 evenly to each of the entire heat sink plates 31 to 36.
[0035] Each of the Fig. 6A, Fig. Figure 6B represents a heat sink plate 131 according to a first modification. The heat sink plate 131 can be used for each of the first heat sink plates 31 up to the sixth heat sink plate 36 in the semiconductor module 10. The heat sink plate 131 according to the first modification is configured such that, as shown in Fig. Figure 6A shows a so-called heat spreader structure. Consequently, as shown in Fig. 6B is shown in a cross-sectional view of the heat sink plate 131, which runs along the line VIB-VIB in Fig. 6A is recorded, a space 131a is formed inside the heat sink plate 131 and the fluid 38 is inside the space 131a in a cross-sectional view of the heat sink plate 131, which runs along the line VIB-VIB in Fig. 6A is included, sealed. Even with such a structure, it is possible to provide anisotropy of the thermal conductivity of the heat sink plate 131. In this situation, the thermal conductivity in the longitudinal direction or a longer side of each of the heat sink plates 31 to 36 is higher than the thermal conductivity in the lateral direction or a shorter side of each of the heat sink plates 31 to 36.
[0036] Each of the Fig. 7A, Fig. Figure 7B represents a heat sink plate 231 according to a second modification. The heat sink plate 231 can be used for each of the first heat sink plates 31 up to the sixth heat sink plate 36 in the semiconductor module 10 described above. As in Fig. As shown in Figure 7B, the heat sink plate 231 according to the second modification in a cross-sectional view of the heat sink plate 231, which extends along the line VIIB-VIIB in Fig. 7A, which is included, has a solid structure made of a conductor such as copper, a metal other than copper, or graphite. In other words, according to the second modification, the fluid is not sealed inside the heat sink plate 231. As described above, in the semiconductor module 10 according to the present embodiment, each of the heat sink plates 31 to 36 has a rectangular outer shape. It is possible to improve the cooling performance and reduce the impedance by arranging the terminals 40, 42, 44, 46, 48 in the lateral direction of the heat sink plates 31 to 36. Even if the heat sink plate 231, which is in the Fig. 7A and Fig. As shown in 7B, the same beneficial effect can be achieved.
[0037] In the semiconductor module 10 according to the present embodiment, the individual semiconductor elements 21 to 26 are each arranged on the corresponding heat sink plates 31 to 36. On the other hand, as in Fig. Figure 8 shows several first semiconductor elements 21 arranged on the first heat sink plate 31. In this case, several first semiconductor elements 21 can be arranged along the longitudinal direction of each of the heat sink plates 31 to 36. With such an arrangement, it is possible to suppress the difference in the current paths generated between the several first semiconductor elements 21 and to achieve uniformity of the currents flowing through each of the several semiconductor elements 21. Similarly, the several semiconductor elements 21 to 26 can also be arranged on the other heat sink plates 32 to 36.
[0038] Although specific examples of the techniques disclosed in this description have been described in detail, these are merely examples and do not limit the scope of this description. The techniques described in this description include various modifications of the specific examples shown above. The technical elements described in this description or in the figures have technical benefits, either individually or in various combinations, and are not limited to the combinations described in this description at the time of filing. The techniques illustrated in this description or in the figures can achieve several objectives simultaneously, and achieving any one of these objectives has technical benefits. QUOTES INCLUDED IN THE DESCRIPTION
[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature
[0000] US 10229895 B2 [0002, 0003]
Claims
[1] Semiconductor module which features: a substrate (12) that is present in a printed circuit board; a semiconductor element (21-26) configured to be located inside the substrate; and a heat sink plate (31-36) on which the semiconductor element is arranged inside the substrate, wherein a fluid (38) is sealed inside the heat sink plate. [2] Semiconductor module according to claim 1, wherein the heat sink plate has an anisotropic thermal conductivity in a top view of the heat sink plate. [3] Semiconductor module according to claim 2, the heat sink plate has a rectangular outer shape, wherein the anisotropic thermal conductivity has at least a first thermal conductivity in a longitudinal direction of the heat sink plate and a second thermal conductivity in a lateral direction of the heat sink plate, and where the first thermal conductivity is greater than the second thermal conductivity. [4] Semiconductor module according to claim 3, further comprising: a plurality of terminals (40, 42, 44, 46, 48), each of which is configured to be exposed on a surface of the substrate, and each of which is further configured to be electrically connected to the semiconductor element inside the substrate, wherein each of the connections is further configured to be positioned so that it is directed towards the heat sink plate in the lateral direction of the heat sink plate. [5] Semiconductor module according to any one of claims 1 to 4, wherein the heat sink plate is one of the elements, heat tube or vapor chamber. [6] Semiconductor module according to any one of claims 1 to 5, wherein the heat sink plate comprises one of the elements, metal or graphite. [7] Semiconductor module according to any one of claims 1 to 6, further comprising: a control circuit (50) configured to be located on an area of the substrate and further configured to control the operation of the semiconductor element.