Semiconductor device

Abstract

The semiconductor device (1) includes a semiconductor module (20) and a fan device (30). The semiconductor module (20) includes a module substrate (21), a first element (22) mounted on the module substrate (21), and a second element (23a) having a smaller heat generation amount and lower heat resistance than the first element (22). In the flow direction of the air flow (F) formed by driving the fan device (30), the fan device (30) is disposed on the more downstream side than the first element (22) and the second element (23a), and the first element (22) is disposed on the more downstream side than the second element (23a).

Description

Technical Field

[0001] The present invention relates to a semiconductor device. Background Art

[0002] A semiconductor device having a semiconductor module is used. In a semiconductor module centered on a system LSI such as a System on a Chip (SoC) or a System in a Package (SiP), since components such as a processor included therein generate heat during operation, cooling is required by air cooling or the like. Therefore, in a semiconductor device, there is a case where a fan device for generating an air flow by driving is provided.

[0003] An example of a semiconductor device having a semiconductor module and a fan device is disclosed in Japanese Unexamined Patent Application Publication No. 2018-113402 (Patent Document 1). In the semiconductor device of Patent Document 1, air is sucked by a fan 42, and an air flow is formed inside a housing 20. A heat generating device 52 and other devices 53 mounted on a substrate 50 are arranged such that the heat generating device 52 is located on the upstream side and the other devices 53 are located on the downstream side in the flow direction of the air flow (see FIG. 11 of Patent Document 1).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2018-113402 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] However, in the structure of the semiconductor device of Patent Document 1, the air flow heated by heat exchange with the heat generating device 52 is supplied to the other devices 53. Therefore, for example, when the heat resistance of the other devices is low, it is necessary to ensure a large gap from the heat generating device 52, which is a main cause of the enlargement of the device. On the contrary, if enlargement is to be avoided, it is necessary to use expensive components with high heat resistance, which is a main cause of high cost.

[0009] Therefore, in a semiconductor device having a semiconductor module and a fan device, it is desired to avoid enlargement and high cost, and to appropriately cool each component mounted on the module substrate.

[0010] Means for Solving the Problems

[0011] The semiconductor device of the present disclosure has a semiconductor module and a fan device, wherein,

[0012] The semiconductor module includes a module substrate, a first element, and a second element mounted on an element arrangement surface on one side of the module substrate.

[0013] The second element is an element with less heat generation and lower heat resistance compared to the first element.

[0014] In the flow direction of the air flow formed by driving the fan device, the fan device is disposed on the downstream side of the first element and the second element, and the first element is disposed on the downstream side of the second element.

[0015] According to this structure, since the first element with relatively large heat generation is disposed on the downstream side of the second element, even if the air flow formed by driving the fan device is heated due to heat exchange with the first element, the influence on the second element is small. Therefore, as the second element, an inexpensive element with not too high heat resistance can be used, and the second element can also be disposed close to the first element. In addition, since only the air flow that cools the second element with relatively small heat generation is supplied to the first element, the cooling performance of the first element can also be ensured. Therefore, in a semiconductor device including a semiconductor module and a fan device, it is possible to avoid enlargement and high cost, and appropriately cool each element mounted on the module substrate.

[0016] The further features and advantages of the technology of the present disclosure will become more apparent from the following description of exemplary and non-limiting embodiments described with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a perspective view of a semiconductor device according to a first embodiment

[0018] Figure 2 is a top view of the semiconductor device

[0019] Figure 3 is a cross-sectional view of the semiconductor device

[0020] Figure 4 is a perspective view of the semiconductor device

[0021] Figure 5 is a perspective view of a semiconductor device according to a second embodiment

[0022] Figure 6 is a cross-sectional view of the semiconductor device DETAILED DESCRIPTION

[0023] (First Embodiment)

[0024] A first embodiment of a semiconductor device will be described with reference to the accompanying drawings. In this embodiment, the semiconductor device is described, for example, as being mounted on a vehicle and configured as an electronic control unit (ECU) that controls in-vehicle information devices. However, of course, the use of the semiconductor device is not limited to this.

[0025] As Figure 1 shown, the semiconductor device 1 includes a main substrate 10, a semiconductor module 20, and a fan device 30. In addition, the semiconductor device 1 further includes a heat sink 40 (see Figure 2 and Figure 3 ). As Figure 3 and Figure 4 shown, these are housed inside the housing 50. The housing 50 is preferably formed in a rectangular parallelepiped shape. It should be noted that Figure 4 is a perspective view in a state where the cover portion is removed to easily visually confirm the inside of the housing 50.

[0026] The main substrate 10 is, for example, a main board. At least the semiconductor module 20 is mounted on one surface, i.e., the first surface 10a, of the main substrate 10. In addition, a main power supply IC 11 and a circuit 12 are mounted on the first surface 10a of the main substrate 10. The main power supply IC 11 is configured to have a power supply function block capable of generating various powers. The circuit 12 is connected to the system LSI 22 included in the semiconductor module 20.

[0027] The semiconductor module 20 includes a module substrate 21, a system LSI 22, a memory 23, and a module power supply IC 24. The module substrate 21 is formed smaller than the main substrate 10. The system LSI 22, the memory 23, and the module power supply IC 24 are mounted on one surface, i.e., the first surface 21a, of the module substrate 21. In addition, the semiconductor module 20 has a first memory 23a and a second memory 23b as the memory 23, and both the first memory 23a and the second memory 23b are mounted on the first surface 21a of the module substrate 21.

[0028] It should be noted that the system LSI 22 is planned to generate heat during operation, and correspondingly has high heat resistance. On the other hand, when the system LSI 22 is operating, only the memory 23 (the first memory 23a and the second memory 23b) that cooperates with the system LSI 22 generates less heat and has lower heat resistance than the system LSI 22. In this embodiment, the system LSI 22 corresponds to the "first element", the first memory 23a corresponds to the "second element", and the second memory 23b corresponds to the "third element". In addition, the first surface 21a on which the system LSI 22, the first memory 23a, and the second memory 23b are commonly mounted corresponds to the "element mounting surface".

[0029] System LSI 22 is a processor that performs various arithmetic processes. In the present embodiment, as Figure 2 shown, a SoC (System on a Chip) is used as the System LSI 22. However, the structure is not limited to this, and a SiP (System in a Package) may also be used as the System LSI 22.

[0030] In addition, as the memories 23 (first memory 23a and second memory 23b), two synchronous dynamic random access memories (SDRAM) are used. The SDRAM is preferably, for example, a DDR3 (Double Data Rate 3, third-generation double data rate) SDRAM, a DDR4 (Double Data Rate 4, fourth-generation double data rate) SDRAM, or the like. However, the structure is not limited to that described above, and a flash memory, a static random access memory (SRAM), or the like may also be used as the memory 23.

[0031] The module power supply IC 24 is configured to have a power supply function block capable of generating at least one kind of electric power.

[0032] As Figure 3 shown, the System LSI 22, the first memory 23a, and the second memory 23b are mounted on the first surface 21a of the module substrate 21 via hemispherical chip terminals 26 regularly arranged on the first surface 21a of the module substrate 21. That is, the semiconductor module 20 is configured as a multi-chip module having a processor, i.e., the System LSI 22, and memories 23 (first memory 23a, second memory 23b) cooperating with the System LSI 22 on the module substrate 21.

[0033] The semiconductor module 20 is mounted on the first surface 10a of the main substrate 10 via hemispherical module terminals 27 regularly arranged between the first surface 10a of the main substrate 10 and the second surface 21b of the module substrate 21, which is the surface opposite to the surface on which the System LSI 22 and the like are mounted.

[0034] The heat sink 40 is formed so as to cover the System LSI 22, the first memory 23a, and the second memory 23b. In the present embodiment, as Figure 2 shown, the heat sink 40 is formed to be about the same size (slightly smaller size) as the module substrate 21.

[0035] The radiator 40 is disposed on the side opposite to the module substrate 21 side with respect to the system LSI 22, the first memory 23a, and the second memory 23b. Moreover, the radiator 40 is disposed in a state of being in contact with the system LSI 22 on the side opposite to the side where the chip terminals 26 are provided in the system LSI 22. The radiator 40 has a raised portion 41 protruding toward the system LSI 22 side, and the protruding end face of the raised portion 41 is in contact with the system LSI 22.

[0036] It should be noted that the radiator 40 does not come into contact with the first memory 23a and the second memory 23b. That is, the radiator 40 is disposed with a gap in the vertical direction (the direction orthogonal to the module substrate 21) with respect to the first memory 23a and the second memory 23b. Preferably, a plurality of fins are provided on the surface of the radiator 40 on the side opposite to the system LSI 22 and the memory 23 side.

[0037] The fan device 30 is an exhaust device for discharging the air inside the housing 50 to the outside of the housing 50. The fan device 30 is rotationally driven by, for example, a fan motor and is composed of an exhaust fan that discharges the air inside the housing 50 to the outside. As Figure 3 and Figure 4 shown, an air intake port 52 for taking in outside air into the housing 50 is further provided on the housing 50. In the present embodiment, the housing 50 has a peripheral wall portion 51 surrounding the semiconductor module 20 and the radiator 40, and the air intake port 52 is provided in the peripheral wall portion 51. It should be noted that when the housing 50 is formed in a rectangular parallelepiped shape as in the present embodiment, preferably, the air intake port 52 and the fan device 30 are separately provided in the portions of the peripheral wall portion 51 facing each other across the semiconductor module 20. In other words, preferably, the air intake port 52 is provided in the peripheral wall portion 51 on the wall portion facing the wall portion where the fan device 30 is provided across the semiconductor module 20.

[0038] As Figure 1 and Figure 2 shown, the fan device 30 is disposed at a position corresponding to the installation area of the semiconductor module 20 in the main substrate 10. The fan device 30 is configured such that the rotation axis of the exhaust fan forms a positional relationship passing through the installation area of the semiconductor module 20.

[0039] In this way, as Figure 2 shown, the air flow F flowing into the housing 50 from the air intake port 52 due to the driving of the fan device 30 and formed inside the housing 50 passes through the semiconductor module 20 and the radiator 40.

[0040] Moreover, the air inlet 52 and the fan device 30 are disposed at positions on the side of the semiconductor module 20 where the system LSI 22 is arranged. Additionally, the air inlet 52 is disposed in the semiconductor module 20 at a position close to the first memory 23a, and the fan device 30 is disposed in the semiconductor module 20 at a position close to the system LSI 22. By doing so, the air flow F formed by the driving of the fan device 30 is easily guided to the periphery of the system LSI 22 with a large amount of heat generation. Therefore, the system LSI 22 can be effectively cooled.

[0041] As Figure 2 and Figure 3 shown, the fan device 30 that discharges the air inside the housing 50 to the outside is naturally arranged on the downstream side of the system LSI 22 and the first memory 23a in the flow direction of the air flow F. In the present embodiment, the system LSI 22 is arranged on the downstream side (the fan device 30 side) of the first memory 23a in the flow direction of the air flow F. Since the system LSI 22 with relatively large heat generation is arranged on the downstream side of the first memory 23a, even if the air flow F is heated by the system LSI 22, the influence on the first memory 23a is small. Therefore, as the first memory 23a, an inexpensive component with not very high heat resistance can be adopted, thereby enabling cost reduction.

[0042] As Figure 2 shown, the second memory 23b is arranged side by side with respect to the system LSI 22 in a direction orthogonal to the flow direction of the air flow F. Here, "arranged side by side in a direction orthogonal to the flow direction of the air flow F" means that the system LSI 22 and the second memory 23b, each having a size occupying a specified range, are arranged with the passage of the air flow F sandwiched therebetween at the same level position in the flow direction of the air flow F as a whole. Therefore, the second memory 23b can be arranged, as in the example shown in Figure 2 , closer to the fan device 30 side than the system LSI 22, or can be arranged farther from the fan device 30 side than the system LSI 22.

[0043] The first memory 23a arranged on the upstream side of the system LSI 22 is less likely to be affected by the heat of the system LSI 22 than the second memory 23b arranged laterally with respect to the system LSI 22. Therefore, in the present embodiment, the arrangement interval D1 between the system LSI 22 and the first memory 23a is set to be narrower than the arrangement interval D2 between the system LSI 22 and the second memory 23b (D1 < D2). That is, the first memory 23a, which is relatively less likely to be affected by the heat of the system LSI 22, is arranged closer to the system LSI 22 than the second memory 23b. Thereby, miniaturization of the entire semiconductor module 20 and further the semiconductor device 1 can be achieved.

[0044] It should be noted that by making the configuration interval D2 between the system LSI 22 and the second memory 23b relatively wide, a nozzle insertion port for filling an underfill material (such as a liquid curable resin like epoxy resin) can be provided in the area between them. Preferably, this nozzle insertion port is a member that is also used for filling the chip terminals 26 of the system LSI 22 and the chip terminals 26 of the second memory 23b.

[0045] As Figure 3 shown, the air flow F formed by the driving of the fan device 30 is divided into an air flow passing above the radiator 40 and an air flow passing below it. For the air flow F passing above the radiator 40, there is no object blocking the passage of this air flow, or even if there is, there are only a plurality of fins of the radiator 40, so this part of the air flow F becomes an air flow extending linearly toward the fan device 30 ( Figure 2 the right part of the dotted arrow in). On the other hand, a part of the air flow F passing below the radiator 40 is blocked from flowing after flowing through the gap between the first memory 23a and the radiator 40, so this part of the air flow F bypasses the raised portion 41 and becomes an air flow in a crank shape when viewed from above toward the fan device 30 ( Figure 2 the left part of the dotted arrow in).

[0046] (Second Embodiment)

[0047] The second embodiment of the semiconductor device will be described with reference to the accompanying drawings. In the semiconductor device 1 of this embodiment, the installation position of the fan device 30 in the housing 50 is different from that of the first embodiment. Hereinafter, the differences between the semiconductor device 1 of this embodiment and the first embodiment will be mainly described. It should be noted that the points not specifically described are the same as those of the first embodiment, and the same reference numerals are used in the drawings and the detailed description is omitted.

[0048] As Figure 5 shown, the housing 50 of this embodiment also has a semiconductor module 20 and a peripheral wall portion 51 surrounding the radiator 40. It should be noted that in Figure 5 the cover portion 53 covering the upper opening of the peripheral wall portion 51 is also shown. In the semiconductor device 1 of this embodiment, an air intake port 52 is provided in the peripheral wall portion 51, and the fan device 30 is provided in the cover portion 53. The air intake port 52 is provided at a position in the peripheral wall portion 51 close to the first memory 23a in the semiconductor module 20. As Figure 6 shown, the fan device 30 is provided above the system LSI 22 in the cover portion 53 (at a position having an overlapping part with the system LSI 22 when viewed from above).

[0049] In this structure, as Figure 6As shown, after the air flow F formed by driving the fan device 30 flows along the radiator 40, it bends upward and faces the fan device 30, becoming an air flow that is substantially L-shaped when viewed from the side.

[0050] (Other Embodiments)

[0051] (1) In the above-described embodiment, the structure in which the semiconductor module 20 includes both the first memory 23a and the second memory 23b as the memory 23 has been described as an example. However, the structure is not limited to this. For example, it may include only the first memory 23a and not the second memory 23b as the memory 23.

[0052] (2) In the above-described embodiment, the structure in which the arrangement interval D1 between the system LSI 22 and the first memory 23a is set to be narrower than the arrangement interval D2 between the system LSI 22 and the second memory 23b has been described as an example. However, the structure is not limited to this. For example, the arrangement interval D1 between the system LSI 22 and the first memory 23a may be set to be equal to the arrangement interval D2 between the system LSI 22 and the second memory 23b. Alternatively, depending on other conditions, the arrangement interval D1 between the system LSI 22 and the first memory 23a may be set to be wider than the arrangement interval D2 between the system LSI 22 and the second memory 23b.

[0053] (3) In the above-described embodiment, the structure in which the semiconductor module 20 is a multi-chip module having the system LSI 22 and the memory 23 that cooperates with the system LSI 22 has been described as an example. However, the structure is not limited to this. For example, the semiconductor module 20 may be constituted by combining a single-chip module having the system LSI 22 and a single-chip module having the memory 23.

[0054] (4) In the above-described embodiment, the structure in which the semiconductor device 1 includes the radiator 40 arranged in a state of being in contact with the system LSI 22 but not in contact with the memory 23 has been described as an example. However, the structure is not limited to this. For example, it may be arranged in a state where the radiator 40 is in contact with both the system LSI 22 and the memory 23. Alternatively, the semiconductor device 1 may not include the radiator 40.

[0055] (5) The structures disclosed in the above-described embodiments (including the above-described embodiment and other embodiments; the same applies hereinafter) can also be used in combination with the structures disclosed in other embodiments as long as there is no contradiction. Regarding other structures, the embodiments disclosed in this specification are illustrative in all aspects, and appropriate changes can be made without departing from the spirit of the present disclosure.

[0056] (Summary of the Embodiment)

[0057] As described above, the semiconductor device of the present disclosure preferably has the following various structures.

[0058] A semiconductor device (1) having a semiconductor module (20) and a fan device (30), wherein

[0059] The semiconductor module (20) includes a module substrate (21), a first element (22), and a second element (23a) mounted on one element arrangement surface (21a) of the module substrate (21).

[0060] The second element (23a) is an element with less heat generation and lower heat resistance compared to the first element (22).

[0061] In the flow direction of the air flow (F) formed by driving the fan device (30), the fan device (30) is disposed on the downstream side of the first element (22) and the second element (23a), and the first element (22) is disposed on the downstream side of the second element (23a).

[0062] According to this structure, since the first element (22) with relatively large heat generation is disposed on the downstream side of the second element (23a), even if the air flow (F) formed by driving the fan device (30) is heated due to heat exchange with the first element (22), the influence on the second element (23a) is small. Therefore, as the second element (23a), a cheap element with not too high heat resistance can be adopted, and the second element (23a) can also be disposed close to the first element (22). In addition, since only the air flow (F) that cools the second element (23a) with relatively small heat generation is supplied to the first element (22), the cooling performance of the first element (22) can also be ensured. Therefore, in the semiconductor device (1) having the semiconductor module (20) and the fan device (30), it is possible to avoid enlargement and high cost, and appropriately cool each element mounted on the module substrate (21).

[0063] As an embodiment,

[0064] Preferably, the semiconductor module (20) further includes a third element (23b) with less heat generation and lower heat resistance compared to the first element (22), and the third element (23b) is mounted on the element arrangement surface (21a).

[0065] The third element (23b) and the first element (22) are arranged side by side in a direction orthogonal to the flow direction of the air flow (F).

[0066] The arrangement interval (D1) between the first element (22) and the second element (23a) is set to be narrower than the arrangement interval (D2) between the first element (22) and the third element (23b).

[0067] The third element (23b) and the first element (22) are arranged in a direction orthogonal to the flow direction of the air flow (F). The second element (23a) is arranged on the upstream side of the first element (22) in the flow direction of the air flow (F). Compared with the third element (23b), it is more difficult for the second element (23a) to receive heat transferred from the first element (22). Thus, with the above structure, by making the arrangement interval (D1) between the first element (22) and the second element (23a) narrower than the arrangement interval (D2) between the first element (22) and the third element (23b), the enlargement of the semiconductor device (1) can be appropriately suppressed.

[0068] As an embodiment,

[0069] Preferably, it further includes a heat sink (40) arranged in contact with the first element (22).

[0070] According to this structure, the heat generated during the operation of the first element (22) can be quickly diffused to the heat sink (40). Moreover, through the heat exchange between the air flow (F) and the heat sink (40), the first element (22) can be cooled more appropriately.

[0071] As an embodiment,

[0072] Preferably, the semiconductor module (20) is a multi-chip module having a processor as the first element (22) and a memory as the second element (23a) that cooperates with the processor on the module substrate (21).

[0073] According to this structure, the semiconductor module (20) composed of a multi-chip module can be miniaturized. Thus, the miniaturization of the semiconductor device (1) can be achieved.

[0074] As an embodiment,

[0075] Preferably, it further includes a housing (50) for accommodating the semiconductor module (20) and an air inlet (52) provided on the housing (50).

[0076] The housing (50) has a peripheral wall portion (51) surrounding the semiconductor module (20).

[0077] The air inlet (52) and the fan device (30) are separately provided at portions of the peripheral wall portion (51) that face each other with the first element (22) and the second element (23a) therebetween.

[0078] According to this structure, the air flow (F) from the air inlet (52) toward the fan device (30) can be appropriately directed toward the semiconductor module (20). Therefore, the first element (22) and the second element (23a) can be appropriately cooled.

[0079] As an embodiment,

[0080] Preferably, it further includes a housing (50) for accommodating the semiconductor module (20) and an air inlet (52) provided on the housing (50),

[0081] The housing (50) has a peripheral wall portion (51) surrounding the semiconductor module (20) and a cover portion (53) covering the upper opening of the peripheral wall portion (51),

[0082] The air inlet (52) is provided on the peripheral wall portion (51), and the fan device (30) is provided on the cover portion (53).

[0083] According to this structure, for example, by disposing the fan device (30) above the semiconductor module (20) in the cover portion (53), the air flow (F) from the air inlet (52) toward the fan device (30) can be appropriately directed toward the semiconductor module (20). Therefore, the first element (22) and the second element (23a) can be appropriately cooled.

[0084] The semiconductor device of the present disclosure can achieve at least one of the above various effects.

[0085] Explanation of reference numerals:

[0086] 1 Semiconductor device

[0087] 20 Semiconductor module

[0088] 21 Module substrate

[0089] 21a First surface (element mounting surface)

[0090] 22 System LSI (first element)

[0091] 23a First memory (second element)

[0092] 23b Second memory (third element)

[0093] 30 Fan device

[0094] 40 Radiator

[0095] 50 Housing

[0096] 51 Peripheral wall portion

[0097] 52 Suction port

[0098] 53 Cover part

[0099] F Airflow

Claims

1. A semiconductor device having a semiconductor module and a fan device, wherein, The semiconductor module includes a module substrate, a first element, and a second element mounted on an element mounting surface on one side of the module substrate. The second element is an element with less heat generation and lower heat resistance than the first element. In the flow direction of the air flow formed by driving the fan device, the fan device is arranged on the downstream side of the first element and the second element, and the first element is arranged on the downstream side of the second element. The semiconductor module further includes a third element with less heat generation and lower heat resistance than the first element, and the third element is mounted on the element mounting surface on one side where the first element and the second element are mounted. The third element and the first element are arranged side by side in a direction orthogonal to the flow direction of the air flow. The arrangement interval between the first element and the second element is set to be narrower than the arrangement interval between the first element and the third element.

2. The semiconductor device according to claim 1, wherein, A heat sink is further included and is arranged in contact with the first element.

3. The semiconductor device according to claim 1 or 2, wherein, The semiconductor module is a multi-chip module having a processor as the first element and a memory cooperating with the processor as the second element on the module substrate.

4. The semiconductor device according to claim 1 or 2, wherein, A housing for accommodating the semiconductor module and an air inlet provided on the housing are further included. The housing has a peripheral wall portion surrounding the semiconductor module. The air inlet and the fan device are separately provided at portions of the peripheral wall portion facing each other with the first element and the second element therebetween.

5. The semiconductor device according to claim 1 or 2, wherein, A housing for accommodating the semiconductor module and an air inlet provided on the housing are further included. The housing has a peripheral wall portion surrounding the semiconductor module and a cover portion covering an upper opening of the peripheral wall portion. The air inlet is provided on the peripheral wall portion, and the fan device is provided on the cover portion.

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