JPH06326226A - Cooling unit - Google Patents

Abstract

PURPOSE:To protect a semiconductor element and the like against fracture by suppressing the pressure drop at the time of feeding refrigerant. CONSTITUTION:A plurality of grooves 2 are made in the main surface of a substrate 1 thus constituting a plurality of fins 7. The top face of the fin 7 is set lower than the peripheral part of the substrate 1, for example, and a gap is provided between the main face of the substrate 1 and the opposing face of a cover plate 3 having through holes 4, 5 applied entirely thereto thus enlarging the channel area when the region, formed between the substrate 1 and the cover plate 3, is utilized as a channel for refrigerant. This constitution realizes a cooling unit in which the pressure drop can be suppressed at the time of feeding refrigerant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device for cooling, for example, a semiconductor element mounted on a substrate.

[0002]

2. Description of the Related Art In recent years, the technological progress of semiconductor devices has been remarkable, and particularly in recent years, there have been strong demands for miniaturization and high integration of semiconductor devices from various fields. In order to meet such a demand, it is necessary to solve the problem relating to the removal of heat generated in the semiconductor device, and the following cooling device has been proposed among them.

An example of a conventional cooling device will be described below with reference to FIG. 9A and 9B show an outline of a conventional cooling device. FIG. 9A is an exploded perspective view, FIG. 9B is an external perspective view, and FIG. 9C is a partial cross-sectional view (AA cross section). Figure).

As shown in the figure, a plurality of grooves 2 are provided on one main surface 1a of the semiconductor substrate 1, and a semiconductor element 6 is provided on the other main surface 1b of the semiconductor substrate 1. . The grooves 2 are provided substantially in parallel at a predetermined interval so that the peripheral portion of the one main surface 1a remains.

A cover plate 3 is attached to one main surface 1a of the semiconductor substrate 1 so as to cover almost the entire surface thereof, and the cover plate 3 has both end portions of each groove 2 described above. Corresponding to, the through holes 4 and 5 extending in the direction orthogonal to the longitudinal direction of each groove 2 are formed. A connection cover (not shown) is attached to these through holes 4 and 5, and they are connected to different coolant flow paths (not shown) as a coolant supply port and a coolant discharge port, respectively. Then, the refrigerant supplied from the refrigerant supply source (not shown) to the one refrigerant passage is
It flows from one coolant channel to one through hole 4, and is fed so as to be distributed to one end of the plurality of grooves 2 provided in the semiconductor substrate 1 here. The sent refrigerant flows through the grooves 2 to the other end side, is collected in the other through hole 5, and is sent out to another refrigerant flow path. In this way, by using the plurality of grooves 2 provided on one main surface of the semiconductor substrate 1 as a coolant flow path and flowing the coolant therein, the semiconductor element 6 provided on the other main surface 1b is cooled. .

However, in the above-mentioned conventional technique, each refrigerant flow path constituted by the plurality of grooves 2 has a very small flow passage cross section and a relatively long flow path length, and therefore, when the refrigerant flows. Pressure loss increases. Therefore, the coolant is less likely to flow in the coolant channel, and the predetermined cooling performance cannot be obtained, which may damage the semiconductor element.

Although the cooling device for the semiconductor element has been described above, such a problem is common not only to the semiconductor element but also to other electronic parts or a cooling device used for a heating element requiring cooling.

Next, a conventional technique relating to a mounting structure of a cooling device for cooling a semiconductor element will be described. Figure 1
FIG. 0 is a sectional view showing a mounting structure of a conventional cooling device. Conventionally, by pressing a metal stud 33 against the back surface of a semiconductor chip 31 on which a semiconductor element is mounted by a spring 32, the heat generated in the semiconductor chip 31 is transferred from the metal stud 33 to the heat conduction plate 34, and finally the refrigerant is formed. Three
The cooling was performed by 5.

However, in this case, the cooling device including the metal studs 33 and the like has a larger structure than the size of the semiconductor chip, which hinders downsizing of the entire electronic device.

[0010]

As described above,
In the conventional cooling device, since the pressure loss when flowing the refrigerant is large, a predetermined cooling performance cannot be obtained, and the semiconductor element or the like may be destroyed. Therefore, in the present invention, such a defect is eliminated, a pressure loss at the time of flowing a refrigerant is reduced, and a cooling device capable of preventing destruction of a semiconductor element or the like is provided, and at the same time, cooling that enables downsizing of an entire electronic device is achieved. It is intended to provide a mounting structure of the device together.

[0011]

In order to achieve the above object, in the present invention, a substrate, a cover plate attached to at least one main surface side of the substrate, and a coolant supply port in the cover plate. A first through hole penetrating in a vertical direction with respect to the substrate provided, and a second through hole penetrating in a vertical direction with respect to the substrate provided in the cover plate as a coolant outlet, A concavo-convex shape is formed on at least one of the opposing surfaces of the substrate or the cover plate, and a gap is formed between a part or all of the convex portions forming the concavo-convex shape and the opposing surface of the substrate or the cover plate. Is provided, and a region formed between the substrate and the cover plate is used as a coolant passage.

[0012]

According to the above-described structure of the present invention, for example, when a concave-convex shape is formed on one main surface side of the substrate and the cover plate is attached to the substrate, the convex portion forming the concave-convex shape, By forming a gap between the facing surface of the cover plate, it is possible to increase the flow passage area when using the region formed between the substrate and the cover plate as a coolant flow passage, The pressure loss when the refrigerant flows can be reduced. Further, by using the cooling device according to the present invention, compact mounting of the cooling device can be realized.

[0013]

Embodiments of the present invention will be described in detail with reference to the drawings. Here, a semiconductor device cooling device will be mainly described, but the present invention is not limited to this case, and can be applied to other electronic components or various heating elements that require cooling.

1 and 2 show a first embodiment of a cooling device according to the present invention. FIG. 1A is an exploded perspective view, FIG. 1B is an external perspective view, and FIGS. 2A to 2D.
FIG. 2 is a partial cross-sectional view showing a cross section taken along the line AA of FIG. Here, the same parts or parts having the same functions as those shown in FIG. 9 are designated by the same reference numerals.

In the cooling device according to this embodiment, for example, a plurality of grooves 2 are formed on one main surface 1a of a rectangular substrate 1 having a side of about 15 mm by a known method such as chemical etching. The fin 7 is configured. The groove 2 is, for example,
The width is about 50 μm and the depth is set to about 300 μm, and the grooves 2 are formed in parallel at substantially equal intervals. Here, the peripheral portion of the substrate 1 is left, and the top surfaces of the fins 7 are made lower in height than the peripheral portion, for example, as shown in FIG.

A cover plate 3 is attached to one main surface 1a of the substrate 1 so as to cover the entire surface thereof, and through holes 4 and 5 are formed in the cover plate 3. A connection cover (not shown) is attached to these through holes 4 and 5, and they are connected to different coolant flow paths (not shown) as a coolant supply port and a coolant discharge port, respectively. Then, the coolant supplied from the coolant supply source (not shown) to the one coolant flow path is sent from the one coolant flow path to the one through hole 4, and passes through the region between the substrate 1 and the cover plate 3, It is sent out from the other through hole 5 to another refrigerant flow path. Thereby, the semiconductor element 6 provided on the other main surface 1b of the substrate 1 is cooled.

FIG. 2 is a partial sectional view showing a section between the substrate 1 and the cover plate 3, that is, a section of the coolant passage provided in the cooling device. In the cooling device according to the present embodiment, for example, as shown in FIG. 2A, a small gap is provided between the top surfaces of the fins 7 and the cover plate 3 and is composed of a plurality of grooves 2. The pressure loss when the refrigerant flows is reduced by connecting different refrigerant channels to increase the channel area. As a result, the refrigerant smoothly flows in the refrigerant passage provided in the cooling device, and a sufficient cooling effect is exerted, so that there is no fear that the semiconductor element to be cooled is destroyed. .

2 (b) to 2 (d) are the same as those shown in FIG.
It is a thing which shows the modification of the refrigerant flow path shown in (a). It is not necessary to provide all the gaps between the top surfaces of the fins 7 and the cover plate 3 for the fins 7, as shown in FIG.
As shown in (b), the top surfaces of the fins 7b may come into contact with the cover plate 3 to divide the refrigerant passage into several parts. In this case, the pressure loss increases to some extent, but the value can be reduced as compared with the conventional case, and the desired effect can be obtained. Further, as shown in FIG. 2C, the height of the fin 7, that is, the gap between the top surface of the fin 7 and the cover plate 3 may not be constant, and the fins 7a, 7
A configuration in which the height is appropriately changed as in c may be adopted. Figure 2
(D) is a combination of (b) and (c),
The same action and effect can be obtained even with such a configuration.

In this embodiment, the fin 7 is formed by providing the groove 2 on the substrate 1 side, but the same effect can be obtained by providing the fin 7 on the cover plate 3 side. Further, the semiconductor element 6 that requires cooling may be provided on the cover plate 3 side.

FIG. 3 shows a second embodiment of the cooling device according to the present invention. 3 (a) is an exploded perspective view, FIG.
(B) is an external perspective view. Here, the same parts or parts having the same functions as those shown in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted. This embodiment is an improvement of the cover plate 3 in the first embodiment. In other words, the cover plate 3 is formed with the through holes 4 at three locations in order to form the supply port and the discharge port for the refrigerant.
a, 4b, 5 are provided. If the through holes 4a and 4b located at both ends of the cover plate 3 are used as the coolant supply ports, the supplied coolant flows from the peripheral portion of the substrate 1 toward the central portion. Then, by applying the remaining through holes 5 as a coolant discharge port, the coolant can be discharged from the vicinity of the central portion of the substrate 1. Since the structure of the fins 7 provided on the substrate 1 is the same as that of the first embodiment (see FIG. 2), duplicate description will be omitted here.

According to the above-mentioned structure, the length of the refrigerant passage is half that of the conventional one, so that it is possible to further reduce the pressure loss in addition to the first embodiment. Therefore, it is possible to construct a cooling device with higher cooling efficiency.

On the other hand, contrary to the above, the through hole 5 located near the central portion of the cover plate 3 is used as the coolant supply port, and the remaining through holes 4a and 4b are used as the coolant discharge ports, whereby the coolant is supplied to the substrate 1. Even if it is supplied from the vicinity of the central portion of the substrate and discharged from the peripheral portion of the substrate 1, the same action and effect as described above can be obtained.

FIG. 4 shows a third embodiment of the cooling device according to the present invention. 4 (a) is an exploded perspective view, FIG.
(B) is an external perspective view. Here, the same parts or parts having the same functions as those shown in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted. This embodiment is an improvement on both the substrate 1 and the cover plate 3 in the first embodiment. In this embodiment,
A partition wall 8 is provided in the center of the substrate 1 so that an independent groove 2a,
2b is provided, and the refrigerant passage has a length that is almost half that of the first embodiment. Correspondingly, the cover plate 3 is provided with through holes 4a, 4b, 5a, 5b at four positions in order to form a coolant supply port and a coolant discharge port. That is, of these through-holes, two through-holes are located in each of the two regions partitioned by the partition wall 8, and one of them is used as a coolant supply port and the other is used as a coolant discharge port. For example, if the through holes 4a and 4b provided at both ends of the cover plate 3 are applied as the coolant supply ports, the coolant flows from the peripheral edge portion of the substrate 1 toward the central portion. Then, the other through hole 5a,
By applying 5b as the coolant outlet, the coolant can be discharged from the vicinity of the central portion of the substrate 1. The structure of the fins 7a and 7b provided on the substrate 1 is the same as that of the first embodiment (see FIG. 2), and therefore the duplicated description is omitted here.

According to the above construction, the length of the refrigerant passage is half that of the conventional one, as in the second embodiment.
In addition to the first embodiment, the pressure loss can be further reduced.

On the other hand, conversely to the above, the through holes 5a and 5b located near the central portion of the cover plate 3 are used as the coolant supply ports, and the remaining through holes 4a and 4b are used as the coolant discharge ports, whereby the coolant is discharged. The supply may be performed from the vicinity of the central portion of the substrate 1 and discharged from the peripheral portion of the substrate 1. In one area, the coolant is supplied from the through holes 4a (4b) at the peripheral edge of the substrate 1 and is discharged from the through holes 5a (5b) near the center of the substrate 1, and in the other area, the opposite. Alternatively, the gas may be supplied from the through hole 5b (5a) near the center of the substrate 1 and discharged from the through hole 4b (4a) at the peripheral edge of the substrate 1.

FIG. 5 and FIG. 6 show a fourth embodiment of the cooling device according to the present invention. 5 (a) is an exploded perspective view, FIG. 5 (b) is an external perspective view, and FIGS. 6 (a) and 6 (b).
FIG. 6 is a partial sectional view showing an AA section of FIG. Here, the same parts as those shown in FIG. 1 or parts having the same functions are designated by the same reference numerals, and the duplicated description will be omitted.

In the first embodiment, the main flow direction of the refrigerant in the cooling device and the longitudinal direction of the groove 2 and the fin 7 are the same, but in the present embodiment, the cover plate 3 is used.
A groove 2 having through holes 4 and 5 formed on the substrate 1 formed on the substrate 1
Further, as a configuration extending in the same direction as the longitudinal direction of the fins 7, the main flow direction of the refrigerant in the cooling device is configured to be orthogonal to the longitudinal directions of the grooves 2 and the fins 7. Therefore, when the refrigerant flows in the refrigerant flow path, the fins 7 disturb the flow and the heat transfer characteristics are improved. Further, as shown in FIGS. 6A and 6B, in this embodiment, it is necessary to provide gaps between the top surfaces of all the fins 7 and the cover plate 3. However, the gap does not have to be constant, and the fins 7a and 7b may have different heights. The other functions and effects are the same as those in the first embodiment.

FIG. 7 shows a fifth embodiment of the cooling device according to the present invention. 7 (a) is an exploded perspective view, FIG.
(B) is a partial sectional view. In this embodiment, the first
On both main surfaces of the intermediate plate 11 corresponding to the substrate 1 in the embodiment,
By forming the plurality of grooves 12a, 12b by a known method such as chemical etching, a plurality of fins 17a, 1
7b. The grooves 12a and 12b are formed in parallel at substantially equal intervals. Here, the peripheral portion of the intermediate plate 11 is left, and the top surfaces of the fins 17a and 17b are, for example, as shown in FIG.
As shown in (a) and (b), the height is made lower than the peripheral portion.

Cover plates 13a and 13b are attached to both main surfaces of the intermediate plate 11 so as to cover the entire surfaces thereof, and these cover plates 13a and 13b constitute a supply port and a discharge port for the refrigerant. Through hole 14
a, 15a and 14b, 15b are provided, respectively. A semiconductor element 16 is provided on the main surface opposite to the main surface connected to the middle plate 11 of the cover plate 13a.

In this embodiment, for example, the through hole 14a of the cover plate 13a and the through hole 15b of the cover plate 13b are used as the refrigerant supply port, and the remaining through holes 15a and 14b are used as the refrigerant discharge port. , Both main surfaces of the intermediate plate 11 and the cover plates 13a, 13b
The refrigerant can be made to flow in a refrigerant flow path provided between and so as to be a counter flow. Thereby, the temperature gradient in the flow direction of the refrigerant is relaxed, and the temperature distribution inside the cooling device can be averaged.

Further, as in the above-mentioned respective embodiments, FIG.
As shown in (b), a fixed gap is provided between the top surfaces of the fins 17a, 17b and the cover plates 13a, 13b,
By connecting the minute refrigerant passages constituted by the plurality of grooves 12a and 12b to increase the passage area, the pressure loss when the refrigerant flows is reduced. As a result, the refrigerant smoothly flows in the refrigerant passage provided in the cooling device, and a sufficient cooling effect is exerted, so that there is no fear that the semiconductor element to be cooled is destroyed. .

Although the semiconductor element 16 is provided only on one cover plate 13a in FIG. 7, it is also provided on the main surface opposite to the main surface connected to the middle plate 11 of the other cover plate 13b. A semiconductor element may be provided and cooled at the same time. Further, the fins 17a and 17b can be considered in the same manner as in the first embodiment (see FIG. 2), and a duplicate description will be omitted here. Further, the present embodiment may be combined with the second to fourth embodiments.

FIG. 8 shows a sixth embodiment of the cooling device according to the present invention. FIG. 8A is an exploded perspective view, FIG.
(B) is a partial sectional view. In the fifth embodiment, the grooves 12a, 12b and the fins 17a, 17b are formed on the intermediate plate 11 to form the refrigerant flow path of the cooling device (see FIG. 7), but in the present embodiment, They are the middle plate 2
Cover plates 23a that are attached to both main surfaces of
It is provided on the facing surface of 23b. That is, the through holes 24a, 25a and 24b, 25b forming the supply port and the discharge port of the refrigerant are provided at two facing positions on the peripheral edge portions of the cover plates 23a, 23b.
A plurality of fins 27a, 27b are formed by forming the grooves 22a, 22b in the portion sandwiched by the through holes on the one main surface of 3a, 23b. The semiconductor element 16 is provided on the main surface opposite to the main surface connected to the middle plate 21 of the cover plate 23a. Even with such a configuration, the same operation and effect as in the fourth embodiment can be obtained.

Next, the mounting structure of the cooling device according to the present invention will be described with reference to FIG. FIG. 11 (a)
Is a sectional view showing an embodiment of a mounting structure of a cooling device according to the present invention, and FIG.

The semiconductor chip 43 connected to the wiring board 41 via the solder bumps 42 is provided with a channel plate 44a having a plurality of grooves of the order of several tens of μm as described above, a coolant supply port and a coolant discharge port. The microchannel heat exchanger 44 formed by pasting together the cover plate 44b which it has is thermally connected. Such thermal connection can be achieved by directly adhering to the semiconductor chip if the microchannel heat exchanger 44 is made of a material having good thermal conductivity such as silicon, and the thermal resistance of the contact portion is sufficiently reduced. It is possible. However, when thermal stress is expected to occur, the connection may be made via an intervening material such as heat conductive grease.

A plurality of microchannel heat exchangers 44 having such a mounting structure are connected to each other, and a coolant supply holder 46 having a coolant passage 45 for supplying a coolant to each is provided. This refrigerant supply holder 4
6 is connected to the cover plate 44b by adhesion or the like, but may be directly connected to the channel plate 44a without providing the cover plate 44b. The coolant passage 46 provided in the coolant supply holder 46 is provided with a passage connected to a coolant supply port and a coolant discharge port provided in the cover plate 44 b of the microchannel heat exchanger 44.

In this way, the microchannel heat exchanger 44, which is a cooling device, is mounted on the semiconductor chip 43, which is a heating element, and the semiconductor chip is driven by the refrigerant flowing in the refrigerant flow passage 45 in the refrigerant supply holder 46. 43 is cooled.

If the microchannel heat exchanger 44 is used as in the present embodiment, the cooling device itself can be downsized, and the total flow rate of the refrigerant can be made small, so that the refrigerant supply holder 46 is also downsized. Thus, the cooling device can be compactly mounted, and the entire electronic device can be made compact.

[0039]

As described above, according to the present invention,
Since it is possible to reduce the pressure loss when the refrigerant flows in the refrigerant passage provided in the cooling device, the refrigerant can smoothly flow in the refrigerant passage, and a sufficient cooling effect can be exhibited. Therefore, it is possible to prevent the semiconductor element or the like to be cooled from being destroyed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of a cooling device according to the present invention.

FIG. 2 is a partial sectional view showing a first embodiment of a cooling device according to the present invention.

FIG. 3 is a perspective view showing a second embodiment of the cooling device according to the present invention.

FIG. 4 is a perspective view showing a third embodiment of the cooling device according to the present invention.

FIG. 5 is a perspective view showing a fourth embodiment of the cooling device according to the present invention.

FIG. 6 is a partial cross-sectional view showing a fourth embodiment of the cooling device according to the present invention.

FIG. 7 is a diagram showing a cooling device according to a fifth embodiment of the present invention.

FIG. 8 is a diagram showing a sixth embodiment of the cooling device according to the present invention.

FIG. 9 is a diagram schematically showing a conventional cooling device.

FIG. 10 is a sectional view showing a mounting structure of a conventional cooling device.

FIG. 11 is a diagram showing a mounting structure of a cooling device according to the present invention.

[Explanation of symbols]

 1 Substrate 2 Groove 3 Cover Plate 4, 5 Through Hole 6 Semiconductor Element 7 Fin 41 Wiring Board 42 Solder Bump 43 Semiconductor Chip 44 Micro Channel Heat Exchanger 45 Refrigerant Flow Path 46 Refrigerant Supply Holder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsumi Kuno 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Inside the Toshiba Research and Development Center (72) Inventor Katsushi Ishizuka Komukai-Toshiba, Kawasaki-shi, Kanagawa Town No. 1 Toshiba Corporation Research & Development Center

Claims (1)

[Claims] 1. A substrate, a cover plate attached to at least one main surface side of the substrate, and a first penetrating hole provided in the cover plate as a coolant supply port in a direction perpendicular to the substrate. And a second through hole that is provided in the cover plate as a coolant discharge port and penetrates in a direction perpendicular to the substrate, and at least one of the facing surface of the substrate or the cover plate has an uneven shape. A gap is formed between a part or all of the convex portion forming the concavo-convex shape and an opposing surface of the substrate or the cover plate, and is formed between the substrate and the cover plate. The cooling device is characterized in that the region is used as a coolant flow path.