Semiconductor module

Abstract

This semiconductor module comprises a substrate, at least one semiconductor element that is positioned on a first surface of the substrate, a heat dissipation member that is positioned above the semiconductor element, and an optic fiber cable that is connected to the semiconductor element. A first direction in which the heat dissipation member extends relative to the semiconductor element and a second direction in which the optic fiber cable extends intersect each other.

Description

Semiconductor Module

[0001] The disclosed embodiments relate to a semiconductor module.

[0002] Conventionally, semiconductor modules have been known in which semiconductor elements (hereinafter also referred to as optical elements) that convert electrical signals into optical signals are mounted on a substrate, and in some cases, these semiconductor modules are connected to optical fiber cables that transmit the converted optical signals from the optical elements to the outside (see Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2020-9824

[0004] The semiconductor module of the present disclosure includes a substrate, at least one semiconductor element located on a first surface of the substrate, a heat dissipation member located above the semiconductor element, and an optical fiber cable connected to the semiconductor element, wherein a first direction in which the heat dissipation member extends relative to the semiconductor element intersects with a second direction in which the optical fiber cable extends.

[0005] FIG. 1 is a perspective view of a semiconductor module according to an embodiment, as seen obliquely from above. FIG. 2 is a perspective view of a semiconductor module according to an embodiment, as seen obliquely from below. FIG. 3 is a plan view of a semiconductor module according to an embodiment. FIG. 4 is a side view of a semiconductor module according to an embodiment. FIG. 5 is a plan view of a semiconductor module according to another embodiment 1. FIG. 6 is a plan view of a semiconductor module according to another embodiment 2. FIG. 7 is a plan view of a semiconductor module according to another embodiment 3. FIG. 8 is a side view of a semiconductor module according to another embodiment 3. FIG. 9 is a cross-sectional view taken along line A-A in FIG. 7. FIG. 10 is a perspective view of a semiconductor module according to another embodiment 4, as seen obliquely from above. FIG. 11 is a cross-sectional view taken along line B-B in FIG. 10.

[0006] Hereinafter, embodiments of the semiconductor module disclosed herein will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the embodiments described below. Furthermore, the embodiments can be appropriately combined as long as the processing content is not contradictory. Furthermore, the same components in the following embodiments are designated by the same reference numerals, and redundant explanations will be omitted.

[0007] Furthermore, in the following embodiments, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "perpendicular," or "parallel" in the strict sense. In other words, the above expressions allow for deviations due to, for example, manufacturing precision, installation precision, etc.

[0008] In addition, in the drawings referred to below, for ease of understanding, an orthogonal coordinate system may be shown in which the X-axis direction, Y-axis direction, and Z-axis direction, which are perpendicular to each other, are defined, and the positive Z-axis direction is the vertically upward direction.

[0009] Conventionally, semiconductor modules have been known in which semiconductor elements (hereinafter also referred to as optical elements) that convert electrical signals into optical signals are mounted on a substrate. These semiconductor modules may be connected to optical fiber cables that transmit the converted optical signals from the optical elements to the outside.

[0010] However, in the above-mentioned conventional technology, heat generated by various elements, such as optical elements, mounted on the semiconductor module can cause uneven heat distribution in the direction of extension of the optical fiber cable, which can degrade the signal quality of the optical signal transmitted through the optical fiber cable.

[0011] Therefore, there is a need for a technology that can overcome the above-mentioned problems and improve the signal quality of optical signals.

[0012] First, the overall configuration of a semiconductor module 1 according to an embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a perspective view of the semiconductor module 1 according to the embodiment as seen obliquely from above, and Fig. 2 is a perspective view of the semiconductor module 1 according to the embodiment as seen obliquely from below.

[0013] In each of the following embodiments, the semiconductor module 1 will be described as an optical module in which an optical element 3 is mounted on a substrate, but the semiconductor module according to the present disclosure does not necessarily have to be an optical module.

[0014] 1 and 2, a semiconductor module 1 according to the embodiment includes a substrate 2, a plurality of optical elements 3 (optical elements 3a to 3d), and a heat dissipation member 4. The optical elements 3 are an example of semiconductor elements.

[0015] The substrate 2 has, for example, a rectangular plate shape in a plan view. In addition to the optical elements 3a to 3d and the heat dissipation member 4, a power supply IC 5, a control IC 6, a chip resistor 7 (all of which are shown in FIG. 3 ) and the like are located on a first surface 21 (here, the top surface) of the substrate 2. Furthermore, a capacitor, a coil, and the like (not shown) may also be located on the first surface 21 of the substrate 2.

[0016] A connector 25 is located on the second surface 22 (here, the lower surface) of the substrate 2. The substrate 2 is electrically connected to a motherboard via the connector 25.

[0017] The optical element 3 is a semiconductor element that converts an electrical signal into an optical signal. Alternatively, the optical element 3 may convert an optical signal into an electrical signal. An interface unit 31 is located on the top surface of each optical element 3. The interface unit 31 is connected to the optical connector 33 via a cable group 32A (see FIG. 3) that is made up of multiple optical fiber cables 32. Hereinafter, when the term "optical fiber cable 32" is used, it may also refer to the cable group 32A based on the relevant drawing.

[0018] The heat dissipation member 4 is a so-called heat sink, and is located above the plurality of optical elements 3. Note that the heat dissipation member 4 does not necessarily have to cover the entire upper surface of the plurality of optical elements 3. In other words, as shown in FIG. 1 , the upper surfaces of the plurality of optical elements 3 may be partially exposed from the heat dissipation member 4.

[0019] The heat dissipation member 4 is located close to the optical elements 3 and dissipates heat generated from the optical elements 3 to the outside of the semiconductor module 1. The heat dissipation member 4 may be in direct contact with the optical elements 3. Alternatively, the heat dissipation member 4 may be in contact with the optical elements 3 via a thermal interface material (TIM). In other words, the heat dissipation member 4 may be thermally connected to the optical elements 3.

[0020] The heat dissipation member 4 may be made of a metal with a relatively high thermal conductivity, such as aluminum, copper, iron, etc. A TIM is a composite material containing a thermally conductive filler in a resin.

[0021] The heat dissipation member 4 has a first portion 41, a plurality of third portions 42, and a plurality of second portions 45. The first portion 41 is a plate-shaped portion disposed opposite the first surface 21 of the substrate 2 with a first gap G1 (see FIG. 11 ) therebetween.

[0022] The third portions 42 are leg-like portions provided on the first portion 41. Specifically, the third portions 42 extend from the first portion 41 toward the substrate 2 and contact the substrate 2 (are placed on the substrate 2). The third portions 42 are also positioned at third intervals G3 (see FIG. 11 ) from one another along the fourth direction D4 (see FIG. 11 ).

[0023] These third portions 42 have a shape in which their thickness is partially increased from the first portion 41. The third portions 42 may be integrated with the first portion 41. The plurality of third portions 42 may be connected to the first portion 41 and the substrate 2. The plurality of third portions 42 extend in a fixed direction (here, the X-axis direction).

[0024] The second portion 45 is located on the surface of the first portion 41 opposite to the surface facing the substrate 2, and extends in the first direction D1 from the first portion 41. Although an example in which the second portion 45 has a pin shape (i.e., a heat dissipation pin) is shown in Figures 1 and 2, the second portion 45 may also have a plate shape (i.e., a heat dissipation fin), for example.

[0025] Next, a detailed configuration of the semiconductor module 1 according to the embodiment will be described with reference to Fig. 3 and Fig. 4. Fig. 3 is a plan view of the semiconductor module 1 according to the embodiment, and Fig. 4 is a side view of the semiconductor module 1 according to the embodiment. Note that in Fig. 3 and Fig. 4, the heat dissipation member 4 is indicated by a dashed line for ease of understanding.

[0026] 4 and other figures, the first direction D1 in which the heat dissipation member 4 extends relative to the optical element 3 is the positive direction of the Z axis. That is, the first direction D1 in which the heat dissipation member 4 dissipates heat is the positive direction of the Z axis. On the other hand, the second direction D2 in which the optical fiber cable 32 extends from the optical element 3 is the positive direction of the X axis.

[0027] That is, in the embodiment, the first direction D1 in which the heat dissipation member 4 extends relative to the optical element 3 and the second direction D2 in which the optical fiber cable 32 extends may intersect. This allows the heat generated in the optical element 3 to be dissipated in a direction away from the optical fiber cable 32, thereby making the temperature distribution in the extension direction of the optical fiber cable 32 uniform.

[0028] Therefore, according to the embodiment, it is possible to prevent deterioration of signal quality due to uneven temperature distribution in the optical fiber cable 32, thereby improving the signal quality of the optical signal.

[0029] 4, the cable group 32A is preferably arranged above the substrate 2 so as to have a portion parallel to the first surface 21. The portion of the cable group 32A parallel to the substrate 2 is preferably located on the side of the cable group 32A that faces the optical element 3 to which the cable group 32A is connected.

[0030] The cable group 32A may be gradually curved in a direction from the optical element 3 side to which the cable group 32A is connected to the end side of the substrate 2 in the direction in which the cable group 32A extends. For example, the cable group 32A may be partially bent near the end of the substrate 2 so as to approach the first surface 21 of the substrate 2 or to come into contact with the first surface 21 of the substrate 2.

[0031] The cable group 32A may be oriented in a direction away from the first surface 21 of the substrate 2 near the end of the substrate 2. This is because the orientation of the cable group 32A changes depending on the arrangement and height of the external circuit device to which the cable group 32A is connected.

[0032] The optical fiber cable 32 (or the cable group 32A) may be parallel to the first surface 21 at least above the substrate 2. This makes it possible to further uniform the temperature distribution in the extension direction of the optical fiber cable 32 (or the cable group 32A).

[0033] In this case, it is preferable that the optical fiber cable 32 (or cable group 32A) extends parallel to the first surface 21 of the substrate 2 over the entire range from the connection point with the optical element 3 above the substrate 2 to the end of the substrate 2.

[0034] This is because if a portion of the optical fiber cable 32 (or cable group 32A) is bent above the substrate 2, the airflow (heat) hitting the bent portion is likely to become turbulent, which can hinder heat dissipation.

[0035] Therefore, according to the embodiment, the signal quality of the optical signal can be further improved.

[0036] 3, the optical elements 3a to 3d are arranged in a direction (Y-axis direction) perpendicular to the extension direction (X-axis direction) of the optical fiber cable 32 when viewed along the extension direction of the optical fiber cable 32. Specifically, the optical elements 3a to 3d are arranged in the positive direction of the Y-axis in the order of optical element 3d, optical element 3c, optical element 3b, and optical element 3a.

[0037] Furthermore, the optical elements 3a to 3d are positioned apart from one another. With this configuration, when multiple optical elements 3a to 3d are positioned on the substrate 2, thermal interference between the optical elements 3a to 3d can be reduced.

[0038] When multiple devices such as optical elements 3a to 3d, which are heat sources, are placed on the same substrate, if the distance between the optical elements 3a to 3d becomes short, the heat generated by each optical element 3a to 3d may be multiplied, causing the temperature of the optical elements 3a to 3d to become higher than when used alone.

[0039] 3, it is possible to prevent the heat generated by each of the optical elements 3a to 3d from increasing synergistically. Placing the power supply IC 5 and chip resistor 7 between the optical fiber cables 32 naturally increases the spacing between the optical elements 3a to 3d.

[0040] 3, among the plurality of optical elements 3a to 3d, optical element 3a and optical element 3b located closest to optical element 3a are misaligned in the extension direction (X-axis direction) of optical fiber cable 32 and in the direction perpendicular to said extension direction (Y-axis direction). Similarly, among the plurality of optical elements 3a to 3d, optical element 3d and optical element 3c located closest to optical element 3d are misaligned in the X-axis direction and Y-axis direction.

[0041] In this way, the plurality of optical elements 3 are arranged with a staggered arrangement, which in this embodiment makes it possible to reduce the size of the substrate 2 while ensuring the distance between adjacent optical elements 3, in other words, while suppressing thermal interference between adjacent optical elements 3.

[0042] Here, an example has been described in which two adjacent optical elements (for example, optical element 3a and optical element 3b) among the plurality of optical elements 3a to 3d are spaced apart in the X-axis direction and the Y-axis direction. However, the present disclosure is not limited to this, and in all of the plurality of optical elements 3a to 3d, the positions of two adjacent semiconductor elements may be shifted in the extension direction of optical fiber cable 32 (X-axis direction) and in a direction perpendicular to this extension direction (Y-axis direction).

[0043] For example, the optical elements 3a to 3d may be arranged in a staggered manner, which also makes it possible to reduce the size of the substrate 2 while suppressing thermal interference between the optical elements 3.

[0044] A blower (not shown), such as a cooling fan, that blows air toward the semiconductor module 1 may be located on the negative X-axis side of the semiconductor module 1. The blower generates air W that blows in the positive X-axis direction.

[0045] The wind W sent from the blower hits the multiple second parts 45 (see Figure 1) and flows along the first surface 21 of the substrate 2, passing through the ventilation passage 100 formed between the substrate 2 and the first part 41 of the heat dissipation member 4.

[0046] In the embodiment, the wind W hits the plurality of optical elements 3 located on the outlet side of the ventilation passage 100, thereby further improving the heat dissipation efficiency of the plurality of optical elements 3.

[0047] Furthermore, in the embodiment, the plurality of optical elements 3 are arranged in a direction (here, the Y-axis direction) that intersects with the flow direction of the wind W, so that the wind W hits all of the optical elements 3 approximately evenly. Therefore, according to the embodiment, the heat dissipation efficiency of the plurality of optical elements 3 can be further improved.

[0048] 3, the control IC 6 may be located below the heat dissipation member 4. The control IC 6 may be thermally connected to the heat dissipation member 4. This allows the heat generated by the control IC 6 to be efficiently dissipated by the heat dissipation member 4.

[0049] For example, a plurality of power supply ICs 5 (four in FIG. 3) may be located on the substrate 2. This allows power to be supplied to the optical element 3 at a plurality of reference voltages (four in FIG. 3).

[0050] Furthermore, when the first surface 21 is viewed in plan, the power supply IC 5 may be located on the opposite side of the control IC 6 with respect to the optical element 3. For example, the control IC 6 may be located on the negative side of the X-axis of the optical element 3, and the power supply IC 5 may be located on the positive side of the X-axis of the optical element 3.

[0051] This reduces interference between the power supply IC 5 and various wirings (not shown) located between the control IC 6 and the optical element 3 on the first surface 21 side of the substrate 2. Therefore, according to the embodiment, it is possible to ensure a degree of freedom in wiring design.

[0052] The plurality of chip resistors 7 may be located in proximity to the corresponding power supply ICs 5. That is, the plurality of chip resistors 7 may be located on the opposite side of the control IC 6 with respect to the optical element 3 when the first surface 21 is viewed in plan.

[0053] In addition, in an embodiment, as shown in Figure 3, at least one of the power supply IC 5 and the chip resistor 7 may be located adjacent to the optical fiber cable 32 but not overlapping with the optical fiber cable 32 when the first surface 21 is viewed in a plane.

[0054] Furthermore, at least one of the power supply IC 5 and the chip resistor 7 is preferably located in a position that does not overlap with the optical element 3 in the X-axis direction when the first surface 21 is viewed in plan.

[0055] Furthermore, it is preferable that both the power supply IC 5 and the chip resistor 7 are located in a position that does not overlap with the optical element 3 when viewed in the X-axis direction when the first surface 21 is viewed in plan.

[0056] For example, at least one of the power supply IC 5 and the chip resistor 7 may be located between adjacent cable groups 32A when the first surface 21 is viewed in plan.

[0057] This reduces a local increase in the temperature of the optical fiber cable 32 due to heat generated from at least one of the power supply IC 5 and the chip resistor 7. That is, in this embodiment, the temperature distribution in the extension direction of the optical fiber cable 32 can be made uniform.

[0058] Therefore, according to the embodiment, the signal quality of the optical signal can be improved.

[0059] In an embodiment, either the power supply IC 5 or the chip resistor 7 may be located in a position that does not overlap with the optical fiber cable 32, or both the power supply IC 5 and the chip resistor 7 may be located in a position that does not overlap with the optical fiber cable 32.

[0060] By positioning both the power supply IC 5 and the chip resistor 7 at locations that do not overlap with the optical fiber cable 32, it is possible to further reduce a local increase in temperature of the optical fiber cable 32. Therefore, according to the embodiment, it is possible to further improve the signal quality of the optical signal.

[0061] <Another Embodiment 1> Next, semiconductor modules 1 according to various other embodiments will be described with reference to Fig. 5 to Fig. 11. Fig. 5 is a plan view of the semiconductor module 1 according to another embodiment 1.

[0062] 5 , in another embodiment 1, the arrangement of the power supply ICs 5 and the chip resistors 7 differs from that of the above-described embodiment. Specifically, in another embodiment 1, all of the optical elements 3 and all of the power supply ICs 5 may be positioned so as not to interfere with each other with respect to the wind W blown from the outside along the first surface 21 of the substrate 2.

[0063] This allows all the optical elements 3 and all the power supply ICs 5 to be efficiently cooled by the wind W.

[0064] In another embodiment, the chip resistors 7 may be positioned upwind of the corresponding power supply ICs 5 with respect to the wind W blown from the outside along the first surface 21 of the substrate 2 .

[0065] This allows the wind W to be applied to both the chip resistors 7 and the power supply ICs 5 that are taller than the chip resistors 7. Therefore, according to another embodiment 1, all of the power supply ICs 5 and all of the chip resistors 7 can be efficiently cooled by the wind W.

[0066] In another embodiment 1, all power supply ICs 5 and all chip resistors 7 are efficiently cooled by wind W, thereby reducing the local increase in temperature of the optical fiber cable 32 due to heat generated from the power supply ICs 5 and chip resistors 7.

[0067] That is, in the first alternative embodiment, it is possible to make uniform the temperature distribution in the extension direction of the optical fiber cable 32. Therefore, according to the first alternative embodiment, it is possible to improve the signal quality of the optical signal.

[0068] Furthermore, it is preferable that the width of the power supply IC 5 be wider than the width of the chip resistor 7. Here, the width refers to the length in a direction parallel to the first surface 21 of the substrate 2. In FIG. 5, this is the length in the Y-axis direction.

[0069] If the width of the power supply IC 5 is larger (wider) than the width of the chip resistor 7 between the power supply IC 5 and the chip resistor 7, when the power supply IC 5 and the chip resistor 7 are arranged on the substrate 2 in the direction in which the wind W flows (in this case, the X-axis direction), the wider power supply IC 5 may be arranged behind the chip resistor 7.

[0070] This is because the wide power supply IC 5 has a portion that protrudes beyond the width of the chip resistor 7, so even if the power supply IC 5 is placed downstream in the direction of the wind W flow, behind the chip resistor 7, the wind W is likely to hit the power supply IC 5 even partially.

[0071] The power supply IC 5 may be larger than the chip resistor 7 in either height (thickness) or width, or may be larger in both height (thickness) and width.

[0072] 6 is a plan view of a semiconductor module 1 according to another embodiment 2. As shown in Fig. 6, the configuration of the heat dissipation member 4 in this embodiment is different from that in the above-described embodiment. Specifically, in this embodiment, the heat dissipation member 4 may be located above the power supply IC 5 and the chip resistor 7 in addition to being located above the optical element 3 and the control IC 6.

[0073] In another embodiment 2, at least one of the power supply IC 5 and the chip resistor 7 may be thermally connected to the heat dissipation member 4. This allows the heat generated from at least one of the power supply IC 5 and the chip resistor 7 to be efficiently dissipated by the heat dissipation member 4.

[0074] In another embodiment 2, at least one of the power supply IC 5 and the chip resistor 7 is thermally connected to the heat dissipation member 4, thereby reducing the local increase in temperature of the optical fiber cable 32 due to heat generated from at least one of the power supply IC 5 and the chip resistor 7.

[0075] That is, in the second alternative embodiment, it is possible to make uniform the temperature distribution in the extension direction of the optical fiber cable 32. Therefore, according to the second alternative embodiment, it is possible to improve the signal quality of the optical signal.

[0076] In another embodiment 2, either the power supply IC 5 or the chip resistor 7 may be thermally connected to the heat dissipation member 4, or both the power supply IC 5 and the chip resistor 7 may be thermally connected to the heat dissipation member 4.

[0077] By thermally connecting both the power supply IC 5 and the chip resistor 7 to the heat dissipation member 4 , the heat generated from both the power supply IC 5 and the chip resistor 7 can be efficiently dissipated by the heat dissipation member 4 .

[0078] <Another Embodiment 3> Fig. 7 is a plan view of a semiconductor module 1 according to another embodiment 3, and Fig. 8 is a side view of the semiconductor module 1 according to another embodiment 3. Fig. 9 is a cross-sectional view taken along line AA shown in Fig. 7.

[0079] 7 , in another embodiment 3, in addition to the heat dissipation member 4, another heat dissipation member 4A may be provided in the semiconductor module 1. The another heat dissipation member 4A may be formed of a metal with a relatively high thermal conductivity, such as aluminum, copper, or iron.

[0080] 7, the heat dissipation member 4A may be disposed on the power supply IC 5 and the chip resistor 7. Alternatively, the heat dissipation member 4A may be positioned so as to extend from above the first surface 21 of the substrate 2, along the side surface 23 of the substrate 2, and around to the peripheral edge of the second surface 22, as shown in FIG.

[0081] In another embodiment 3, at least one of the power supply IC 5 and the chip resistor 7 may be thermally connected to another heat dissipation member 4 A. This allows the heat generated from at least one of the power supply IC 5 and the chip resistor 7 to be efficiently dissipated by the other heat dissipation member 4 A.

[0082] Furthermore, by thermally connecting at least one of the power supply IC 5 and the chip resistor 7 to another heat dissipation member 4A, the local increase in temperature of the optical fiber cable 32 due to heat generated from at least one of the power supply IC 5 and the chip resistor 7 can be reduced.

[0083] That is, in the third alternative embodiment, it is possible to make uniform the temperature distribution in the extension direction of the optical fiber cable 32. Therefore, according to the third alternative embodiment, it is possible to improve the signal quality of the optical signal.

[0084] 8 , in another embodiment 3, the third direction D3 in which the other heat dissipation member 4A dissipates heat may be oriented in a direction different from the first direction D1 in which the heat dissipation member 4 dissipates heat. For example, the first direction D1 in which the heat dissipation member 4 dissipates heat may be the positive direction of the Z axis, and the third direction D3 in which the other heat dissipation member 4A dissipates heat may be the negative direction of the Z axis.

[0085] This allows the optical element 3, the power supply IC 5, the control IC 6, and the chip resistor 7 located on the first surface 21 of the substrate 2 to be cooled more efficiently.

[0086] In another embodiment 3, by directing the third direction D3 in which another heat dissipation member 4A dissipates heat toward the second surface 22 of the substrate 2, it is possible to reduce the local increase in temperature of the optical fiber cable 32 due to heat generated from at least one of the power supply IC 5 and the chip resistor 7.

[0087] That is, in the third alternative embodiment, it is possible to make uniform the temperature distribution in the extension direction of the optical fiber cable 32. Therefore, according to the third alternative embodiment, it is possible to improve the signal quality of the optical signal.

[0088] 9, in another embodiment 3, the heat dissipation member 4A and the optical fiber cable 32 may be spaced apart from each other. This reduces the heat transfer from the heat dissipation member 4A to the optical fiber cable 32, thereby making it possible to uniform the temperature distribution in the extending direction of the optical fiber cable 32.

[0089] Therefore, according to the third alternative embodiment, the signal quality of the optical signal can be improved.

[0090] In another embodiment 3, a heat insulating member may be located between the heat dissipation member 4A and the optical fiber cable 32. This also makes it possible to reduce the heat transfer from the heat dissipation member 4A to the optical fiber cable 32.

[0091] 9, the heat dissipation member 4A may have a substantially C-shape in cross section, which allows the heat dissipation member 4A to be fixed to the substrate 2 by fitting the heat dissipation member 4A from above the substrate 2.

[0092] Therefore, according to the third alternative embodiment, the heat dissipation member 4A can be easily attached to the substrate 2.

[0093] Alternative Embodiment 4 FIG. 10 is a perspective view of a semiconductor module 1 according to alternative embodiment 4, as seen obliquely from above, and FIG. 11 is a cross-sectional view taken along line BB in FIG.

[0094] 10 and 11 , in another embodiment 4, the configuration of the second portion 45 of the heat dissipation member 4 differs from that of the above-described embodiment (see FIG. 1 ). Specifically, in another embodiment 4, the second portion 45 may be a plate-shaped heat dissipation fin extending from the first portion 41 along the first direction D1.

[0095] In another embodiment 4, for example, as shown in FIG. 11, multiple second portions 45 are positioned at a second interval G2 from each other along a fourth direction D4 (e.g., the Y-axis direction) that intersects with the second direction D2 (see FIG. 10).

[0096] This allows the dimension S1 of the second portion 45 in the fourth direction D4 to be smaller than when the second portion 45 is a heat dissipation pin, thereby making it possible to reduce the weight of the heat dissipation member 4.

[0097] 10, in another embodiment 4, second gaps G2 (see FIG. 11) between adjacent second portions 45 may extend along the second direction D2. This allows wind W (see FIG. 3) sent from a blower (not shown) to flow smoothly along the second gaps G2, so that the wind W hits all of the second portions 45 approximately evenly.

[0098] Therefore, according to the fourth alternative embodiment, the heat dissipation efficiency of the heat dissipation member 4 can be further improved.

[0099] 11 , in another embodiment 4, the dimension S1 of the second portion 45 in the fourth direction D4 may be smaller than the dimension S2 of the third portion 42 in the fourth direction D4. In this way, by reducing the dimension S1 of the second portion 45 (i.e., by making the second portion 45 thinner), it is possible to achieve a desired heat dissipation efficiency even if the heat dissipation member 4 is made smaller and thinner.

[0100] That is, in another embodiment 4, by making the dimension S1 of the second portion 45 smaller than the dimension S2 of the third portion 42, the thickness of the third portion 42 can be ensured to stably fix the heat dissipation member 4 to the substrate 2, and the second portion 45 can be made thinner to achieve a smaller and lower-profile heat dissipation member 4. Note that in the present disclosure, the dimension S1 of the second portion 45 in the fourth direction D4 may be, for example, 0.5 mm to 1.0 mm, and more specifically, approximately 0.6 mm. The dimension S2 of the third portion 42 may be, for example, 1 mm or more.

[0101] In another embodiment 4, when the dimension of the second gap G2 in the fourth direction D4 is S3, the dimension S4 of the interface portion 31 in the fourth direction D4 may satisfy the following formula (1): S4≧2×S1+2×S3 (1)

[0102] In other words, the dimensions of the heat dissipation member 4 should be determined based on the dimension S4 in the fourth direction D4 of the interface portion 31 so that not only the thickness of the second portion 45 (i.e., dimension S1) but also the pitch of the multiple second portions 45 (i.e., dimension S3) is reduced.

[0103] This allows an increase in the number of second portions 45 that can be arranged on the upper surface of the first portion 41, thereby further improving the heat dissipation efficiency of the heat dissipation member 4. Furthermore, since the desired heat dissipation efficiency can be achieved even if the heat dissipation member 4 is made small and low-profile, the heat dissipation member 4 can be made small and low-profile.

[0104] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present disclosure.

[0105] Further advantages and other aspects may readily occur to those skilled in the art. Therefore, the disclosure in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

[0106] The present technology may also be configured as follows: (1) A semiconductor module comprising: a substrate; at least one semiconductor element located on a first surface of the substrate; a heat dissipation member located above the semiconductor element; and an optical fiber cable connected to the semiconductor element, wherein a first direction in which the heat dissipation member extends relative to the semiconductor element intersects with a second direction in which the optical fiber cable extends. (2) The semiconductor module according to (1), wherein the optical fiber cable has a portion parallel to the first surface at least above the substrate. (3) The semiconductor module according to (1) or (2), further comprising: at least one power supply IC located on the first surface and supplying power to the semiconductor element; and at least one chip resistor located on the first surface and electrically connected to the power supply IC, wherein at least one of the power supply IC and the chip resistor is located adjacent to the optical fiber cable but does not overlap with the optical fiber cable when the first surface is viewed in plan. (4) The semiconductor module according to (3), wherein the semiconductor element and the power supply IC are positioned so as not to interfere with each other with respect to air blown from the outside along the first surface of the substrate. (5) The semiconductor module according to (3) or (4), wherein the chip resistor is positioned upwind of the power supply IC with respect to air blown from the outside along the first surface of the substrate. (6) The semiconductor module according to any one of (3) to (5), wherein at least one of the power supply IC and the chip resistor is thermally connected to the heat dissipation member. (7) The semiconductor module according to any one of (3) to (5), wherein at least one of the power supply IC and the chip resistor is thermally connected to another heat dissipation member. (8) The semiconductor module according to (7), wherein a third direction in which the another heat dissipation member dissipates heat is different from the first direction.(9) The semiconductor module according to any one of (1) to (8), wherein the heat dissipation member has at least a plate-shaped first portion positioned opposite the substrate and at a first interval from the substrate, and a plurality of second portions extending from the first portion along the first direction, wherein the second portions are plate-shaped heat dissipation fins extending along the first direction. (10) The semiconductor module according to (9), wherein the plurality of second portions are positioned at a second interval from each other along a fourth direction intersecting the second direction, and the second interval extends along the second direction. (11) The semiconductor module according to (10), wherein the heat dissipation member further has a plurality of third portions extending from the first portion toward the substrate and in contact with the substrate, and positioned at a third interval from each other along the fourth direction, wherein a dimension of the second portions in the fourth direction is smaller than a dimension of the third portions in the fourth direction.

[0107] REFERENCE SIGNS LIST 1 Semiconductor module 2 Substrate 21 First surface 3, 3a to 3d Optical element (an example of a semiconductor element) 32 Optical fiber cable 4 Heat dissipation member 41 First part 42 Third part 45 Second part 4A Another heat dissipation member 5 Power supply IC 6 Control IC 7 Chip resistor D1 First direction D2 Second direction D3 Third direction D4 Fourth direction G1 First gap G2 Second gap G3 Third gap S1 to S4 Dimensions W Wind

Claims

1. A substrate, at least one semiconductor element located on a first surface of the substrate, a heat dissipation member located above the semiconductor element, an optical fiber cable connected to the semiconductor element, comprising: a semiconductor module in which a first direction in which the heat dissipation member extends with respect to the semiconductor element and a second direction in which the optical fiber cable extends intersect.

2. The optical fiber cable has a portion parallel to the first surface at least above the substrate. The semiconductor module according to claim 1.

3. at least one power supply IC located on the first surface and supplying power to the semiconductor element, at least one chip resistor located on the first surface and electrically connected to the power supply IC, further comprising: at least one of the power supply IC and the chip resistor is located adjacent to the optical fiber cable and does not overlap with the optical fiber cable when the first surface is viewed in plan. The semiconductor module according to claim 1 or 2.

4. With respect to the wind sent along the first surface of the substrate from the outside, the semiconductor element and the power supply IC are located in non-interfering positions with respect to each other. The semiconductor module according to claim 3.

5. With respect to the wind sent along the first surface of the substrate from the outside, the chip resistor is located upstream of the power supply IC with respect to the wind. The semiconductor module according to claim 3.

6. At least one of the power supply IC and the chip resistor is thermally connected to the heat dissipation member. The semiconductor module according to claim 3.

7. At least one of the power supply IC and the chip resistor is thermally connected to another heat dissipation member. The semiconductor module according to claim 3.

8. A third direction in which the another heat dissipation member dissipates heat is different from the first direction. The semiconductor module according to claim 7.

9. The heat dissipation member has at least a plate-shaped first portion located at a first interval from and facing the substrate, and a plurality of second portions extending along the first direction from the first portion, The second portion is a plate-shaped heat dissipation fin extending along the first direction. The semiconductor module according to claim 1 or 2.

10. The plurality of second portions are located at a second interval from each other along a fourth direction intersecting the second direction, and The second interval extends along the second direction. The semiconductor module according to claim 9.

11. The heat radiating member further has a plurality of third portions that extend from the first portion toward the substrate, are in contact with the substrate, and are positioned at a third interval from each other along the fourth direction, wherein the dimension of the second portion in the fourth direction is smaller than the dimension of the third portion in the fourth direction. The semiconductor module according to claim 10.