Cooling device

Abstract

Cooling device (100) that cools a semiconductor device (2) mounted on a surface of a substrate (1), the cooling device comprising: a base (10) attached to a rear surface of the substrate; a plurality of ribs (11) projecting from the base; and a base plate (12, 12b) which is arranged spaced apart from the base, wherein a recessed section (10r) which is recessed towards a substrate side, is formed in an area which is a surface of the base facing a base plate side and corresponds to the semiconductor device; characterized in that Among the majority of ribs, the distance between ribs provided in the recessed section is narrower than the distance between ribs other than those provided in the recessed section.

Description

Technical field

[0001] The present disclosure relates to a cooling device. State of the art

[0002] For example, a device for cooling semiconductor components (chips) is known as the one disclosed in patent document 1 below. In the device disclosed in patent document 1 below, a recess is formed in a housing to which semiconductor components are attached, and a metal base with a plate shape is attached to cover the recess. The semiconductor components are mounted on the metal base, and a cooling water channel is formed directly beneath the semiconductor components. List of literature on patent literature

[0003] Patent Document 1: JP 2003-116282 A

[0004] Further state of the art can be found in document DE 11 2010 000 026 T5 which describes a semiconductor module, in document DE 11 2013 004 552 T5 which describes a semiconductor device and a method for manufacturing a semiconductor device, and in document DE 11 2008 000 452 T5 which describes a semiconductor module and an inverter device. Brief description of the invention: Technical problem

[0005] However, if the metal base simply has a plate shape as described above, it will exhibit high thermal resistance between the refrigerant and the semiconductor devices. This may result in inefficient cooling of the semiconductor devices.

[0006] The present invention was made to solve the above problem, and one object of the present invention is to provide a cooling device with further improved cooling efficiency. Solution to the problem

[0007] To solve the aforementioned problem, a cooling device according to the present disclosure cools semiconductor devices mounted on the surface of a substrate. The cooling device includes a base attached to a rear surface of the substrate, a plurality of ribs projecting from the base, and a bottom plate supporting the plurality of ribs between the base and the bottom plate. A recessed section, recessed towards the base side, is formed in a region that is a surface of the base facing the bottom plate side and corresponding to the semiconductor devices.

[0008] The present invention is defined by the independent claims. The dependent claims describe optional features and preferred embodiments. Advantageous effects of the invention

[0009] According to the present disclosure, a cooling device with further improved cooling efficiency can be provided. Brief description of the drawings Fig. Figure 1 is a cross-sectional view illustrating the configuration of a cooling device according to a first embodiment of the present disclosure. Fig. Figure 2 is a cross-sectional view illustrating the configuration of a cooling device according to a second embodiment of the present disclosure. Fig. Figure 3 is a cross-sectional view illustrating the configuration of a cooling device according to a third embodiment of the present disclosure. Fig. Figure 4 is a cross-sectional view illustrating the configuration of a cooling device according to a fourth embodiment of the present disclosure. Fig. Figure 5 is a top view of ribs according to a further development of the individual embodiments of the present disclosure. Description of embodiments: First embodiment; Configuration of substrate and cooling device

[0010] Below, a cooling device 100 according to a first embodiment of the present disclosure is described with reference to the Fig. 1 described. The cooling device 100 is a device for cooling semiconductor components 2, which are mounted on a substrate 1, by means of a liquid refrigerant. As described in Fig. As illustrated in Figure 1, the substrate 1 includes copper structures 1a and 1c, a substrate main body 1b and bonding materials 1d and 2a.

[0011] The main substrate body 1b is formed, for example, from a glass epoxy resin or a Bakelite resin in a sheet form. The copper structures 1a and 1c are deposited on the surface and the back surface, respectively, of the main substrate body 1b. The desired printed wiring is formed by etching onto the copper structures 1a and 1c. The bonding material 2a is provided for attaching the semiconductor devices 2 to the copper structure 1a.

[0012] A plurality of semiconductor devices 2 (three in one example) are arranged on the substrate 1. The semiconductor device 2 is, for example, a power transistor or a power FET and generates heat during operation. These semiconductor devices 2 are arranged at intervals from one another on the substrate 1. Furthermore, the semiconductor devices 2 are electrically connected to the aforementioned copper structure 1a.

[0013] Next, the configuration of cooling device 100 will be described. As in Fig. As illustrated in Figure 1, the cooling device 100 includes a base 10 and a bottom plate 12. The base 10 and the bottom plate 12 are formed in one piece from a metal material with good thermal conductivity, such as aluminum or copper. It is also possible to form the cooling device 100 by additive manufacturing (AM forming process).

[0014] The base 10 is attached to the rear surface of the protruding substrate 1 (i.e., a surface facing away from the surface on which the semiconductor devices 2 are mounted) by the bonding material 1d. The base 10 has a plate shape with a larger area than the substrate 1. As described in detail below, a recessed section 10r, facing the side of the protruding substrate 1, is formed in a central section (i.e., a central section of an area corresponding to the majority of semiconductor devices) on a rear surface 10b of the base 10. In other words, in the area where the recessed section 10r is formed, the plate thickness of the base 10 is less than in other areas. Furthermore, the cross-sectional shape of the recessed section 10r is triangular only as an example. The recessed section 10r could have a rectangular or arcuate cross-section.Furthermore, the recessed section 10r is a groove that extends over the entire length of the base 10. Operational impact

[0015] The following describes the operation of the cooling device 100 described above. When the semiconductor devices 2 are operated, they generate heat due to internal resistance or similar factors. When the majority of semiconductor devices 2 are integrated and arranged as described above, the temperature is particularly high in the central section of the integrated area due to thermal interference. If such heat generation increases, thermal runaway or damage to the semiconductor devices 2 may occur. Therefore, the present embodiment uses a configuration in which the semiconductor devices 2 are cooled by the cooling device 100.

[0016] First, a refrigerant introduced from the outside into a flow path F is circulated through the flow path F in the direction in which the recessed section 10r extends. During this process, the semiconductor devices 2 are cooled via the base 10 by heat absorption caused by the refrigerant. However, if the base 10, unlike in the preceding embodiment, simply has a plate shape, it exhibits a high thermal resistance between the refrigerant and the semiconductor devices 2. Therefore, the semiconductor devices may not be cooled efficiently. For this reason, in the present embodiment, the recessed section 10r is formed in the base 10.

[0017] According to the configuration described above, the recessed section 10r is formed in an area of ​​the base 10 corresponding to the semiconductor devices 2. This allows the thermal resistance of the base 10 to be reduced compared to other areas. As a result, heat transfer between the refrigerant and the semiconductor devices 2 is enhanced, and the semiconductor devices 2 can be cooled efficiently. Furthermore, compared to a case where the thickness of the entire base 10 is reduced, the recessed section 10r is formed only in a portion of the base, thus mitigating a decrease in the compressive strength of the base 10 with respect to the refrigerant pressure.

[0018] The first embodiment of the present invention has been described above. It should be noted that various modifications and further developments can be made to the configurations described above without departing from the essence of the present invention. Second embodiment

[0019] Next, a second embodiment of the present invention will be described with reference to Fig. 2 described. The same components as in the first embodiment are provided with the same reference numerals, and a detailed description of them is omitted. As in Fig. As illustrated in Figure 2, in the present embodiment a plurality of ribs 11 are provided on the rear surface 10b of the base 10. Each of the ribs 11 projects in a direction away from the base 10. Furthermore, the plurality of ribs 11 are arranged at intervals in the direction in which the recessed section 10r extends.

[0020] The projecting ribs 11 are supported by the base plate 12 between the base 10 and the base plate 12. A space enclosed by the base 10 and the base plate 12 forms the flow path F for circulating an externally introduced refrigerant. In the present embodiment, a surface of the base plate 12 on the side facing the base 10 is flat. The recessed section 10r is a groove extending over the entire length of the base 10, and the majority of ribs 11 extend in a plate-like shape in the direction of the groove (the recessed section 10r).

[0021] According to the above configuration, the contact area between the refrigerant and the cooling device is increased by the fins 11, so that the cooling efficiency can be further improved.

[0022] Furthermore, according to the above configuration, the fins 11 extend in the direction of the groove to reduce the possibility of the refrigerant flow being obstructed by the fins 11. Accordingly, the refrigerant flow rate is ensured and the semiconductor devices 2 can be cooled more efficiently.

[0023] The second embodiment of the present invention has been described above. It should be noted that various modifications and further developments can be made to the configurations described above without departing from the essence of the present invention. Third embodiment

[0024] Next, a third embodiment of the present invention will be described with reference to Fig. 3 described. The same components as in the first embodiment are provided with the same reference numerals, and a detailed description of them is omitted. As in Fig. As illustrated in Figure 3, in the cooling device 100 of the present embodiment, the distance between the ribs 11 provided in the recessed section 10r is narrower under the majority of ribs 11 than between the other ribs 11.

[0025] According to the configuration described above, the spacing between the fins 11 provided in the recessed section 10r is narrow, ensuring a large contact area between these fins 11 and the refrigerant compared to other areas. This allows for more efficient cooling of the semiconductor devices 2.

[0026] The third embodiment of the present invention has been described above. It should be noted that various modifications and further developments can be made to the configurations described above without departing from the essence of the present invention. Fourth embodiment

[0027] Next, a fourth embodiment of the present invention will be described with reference to Fig. 4 described. Identical components as in the embodiments described above are identified by the same reference numerals, and a detailed description thereof is omitted. As in Fig. As illustrated in Figure 4, the shape of a base plate 12b in the present embodiment differs from that in the first embodiment. In particular, a convex section 12t with a shape corresponding to the recessed section 10r is formed in a region of the base plate 12b that faces the recessed section 10r. That is to say, in the example of Fig. 4 is the convex section 12t with a triangular cross-sectional shape provided, which corresponds to the recessed section 10r with a triangular cross-sectional shape. According to the above configuration, the

[0028] The cross-sectional area of ​​the flow path F between a region located between the recessed section 10r and the convex section 12t in the flow path F and the other regions remains constant. Consequently, the possibility of stagnation or pressure drop when the refrigerant flows into the recessed section 10r, for example, can be reduced. Accordingly, the refrigerant can circulate more stably, allowing the semiconductor devices 2 to be cooled more efficiently.

[0029] The fourth embodiment of the present invention has been described above. It should be noted that various modifications and further developments can be made to the configurations described above without departing from the essence of the present invention. For example, in each of the preceding embodiments, an example was described in which only one recessed section 10r is formed in the central section of the plurality of semiconductor devices 2. However, the number of recessed sections 10r is not limited to one, and one recessed section 10r can also be formed for each of the semiconductor devices 2. In such a case, it is desirable that the convex sections 12t described in the fourth embodiment be provided in the same number as the recessed sections 10r.Furthermore, the flow direction of a refrigerant does not necessarily coincide with the direction in which the fins 11 extend, and may be a direction that intersects the direction in which the fins 11 extend. Moreover, the shape of the fin 11 is not limited to a plate shape, and as in . Fig. As illustrated in Figure 5, pins 11' can also be used instead of the ribs 11. In such a case, as described in the third embodiment, the distance between the pins 11' provided in the recessed section 10r can also be narrower than that between the other pins 11'. Notes

[0030] The cooling device 100 according to the individual embodiments can be understood, for example, as follows.

[0031] (1) The cooling device 100 according to the first point cools the semiconductor devices 2 mounted on a surface of the substrate 1. The cooling device 100 includes the base 10, which is attached to a rear surface of the substrate, and the base plate 12, which is spaced apart from the base 10, and the recessed section 10r, which is recessed towards the side of the substrate 1, is formed in a region which is a surface of the base 10 and corresponds to the semiconductor devices 2, the surface of which faces the side of the base plate 12.

[0032] According to the configuration described above, the recessed section 10r is formed in an area within the base 10 that corresponds to the semiconductor devices 2. This allows the thermal resistance of the base 10 to be reduced compared to other areas. As a result, heat transfer between the refrigerant and the semiconductor devices 2 is enhanced, and the semiconductor devices 2 can be cooled efficiently.

[0033] (2) The cooling device 100 according to the second point further includes the plurality of ribs 11 projecting from the base 10.

[0034] According to the above configuration, the contact area between the refrigerant and the cooling device is increased by the fins 11, so that the cooling efficiency can be further improved.

[0035] (3) In the cooling device 100 according to the third point, the recessed section 10r is a groove extending over the entire length of the base 10, and the majority of ribs 11 extend in a plate shape in the direction in which the groove extends.

[0036] According to the configuration described above, the fins 11 extend in the direction of the groove, thus reducing the possibility of the refrigerant flow being obstructed by the fins 11. Consequently, the refrigerant flow rate is ensured and the semiconductor devices 2 can be cooled more efficiently.

[0037] (4) In the cooling device 100 according to the fourth point, the distance between the ribs 11 provided in the recessed section 10r is narrower under the majority of ribs 11 than between the other ribs 11.

[0038] According to the configuration described above, the spacing between the fins 11 provided in the recessed section 10r is narrow, ensuring a large contact area between these fins 11 and the refrigerant compared to other areas. This allows for more efficient cooling of the semiconductor devices 2.

[0039] (5) In the cooling device 100 according to the fifth point, the convex section 12t is formed in a region of the base plate 12b which faces the recessed section 10r and has a shape corresponding to the recessed section 10r. According to the above configuration, the

[0040] The cross-sectional area of ​​the flow path F between a region located between the recessed section 10r and the convex section 12t, and the other regions, is constant. As a result, for example, the possibility of stagnation or pressure loss when the refrigerant flows into the recessed section 10r can be reduced.

[0041] (6) The cooling device 100 according to the sixth point further includes the plurality of pins 11' projecting from the base 10.

[0042] According to the above configuration, the contact area between the refrigerant and the cooling device is increased by the pins 11', so that the cooling efficiency can be further improved.

[0043] (7) In the cooling device 100 according to the seventh point, the distance between the pins 11' among the majority of pins 11' provided in the recessed section 10r is narrower than that between the other pins 11'.

[0044] According to the above configuration, the distance between the pins 11' provided in the recessed section 10r is narrow, ensuring a large contact area between these pins 11' and the refrigerant compared to other areas. This allows for more efficient cooling of the semiconductor devices 2.

[0045] (8) In the cooling device 100 according to the eighth point, the convex section 12t is formed in a region of the base plate 12b which faces the recessed section 10r, having a shape corresponding to the recessed section 10r.

[0046] According to the configuration described above, the cross-sectional area of ​​the flow path F between the area located between the recessed section 10r and the convex section 12t, and the other areas, is constant. As a result, for example, the possibility of stagnation or pressure loss when the refrigerant flows into the recessed section 10r can be reduced. List of reference symbols 100 Cooling device 1 substrate 1a, 1c Copper structure 1b Substrate main body 1D bonding material 2 Semiconductor device 2a Bonding material 10 Base 10b rear surface 11th rib 11' pen 12, 12b Base plate 12t convex section

Claims

[1] Cooling device (100) for cooling a semiconductor device (2) mounted on a surface of a substrate (1), the cooling device comprising: a base (10) attached to a rear surface of the substrate; a plurality of ribs (11) projecting from the base; and a base plate (12, 12b) which is arranged spaced apart from the base, wherein a recessed section (10r) which is recessed towards a substrate side, is formed in an area which is a surface of the base facing a base plate side and corresponds to the semiconductor device; characterized by , that Among the majority of ribs, the distance between ribs provided in the recessed section is narrower than the distance between ribs other than those provided in the recessed section. [2] Cooling device according to claim 1, wherein the recessed section is a groove that extends over the entire length of the base, and The majority of ribs extend in a plate shape in the same direction as the groove. [3] Cooling device according to one of claims 1 to 2, wherein a convex section (12t) with a shape corresponding to the recessed section is formed in a region of the base plate which faces the recessed section. [4] Cooling device (100) for cooling a semiconductor device (2) mounted on a surface of a substrate (1), the cooling device comprising: a base (10) attached to a rear surface of the substrate; a plurality of pins (11') projecting from the base; and a base plate (12, 12b) which is arranged spaced apart from the base, wherein a recessed section that is recessed towards a substrate side, is formed in an area that is a surface of the base facing a base plate side and corresponds to the semiconductor device; characterized by , that Among the majority of pins, the distance between pins provided in the recessed section is narrower than the distance between pins other than those provided in the recessed section. [5] Cooling device according to claim 4, wherein a convex section (12t) with a shape corresponding to the recessed section is formed in a region of the base plate which faces the recessed section.

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