WO2012025981A1

WO2012025981A1 - Cooling apparatus, electronic apparatus having cooling apparatus, and method for cooling heat generating body

Info

Publication number: WO2012025981A1
Application number: PCT/JP2010/064197
Authority: WO
Inventors: 林　信幸; 米田　泰博; 中西　輝; 将森田
Original assignee: 富士通株式会社
Priority date: 2010-08-23
Filing date: 2010-08-23
Publication date: 2012-03-01
Also published as: US20130139998A1; JPWO2012025981A1; JP5590128B2

Abstract

Provided is a cooling apparatus which has: a first cooling section, which cools, with a first refrigerant liquid having insulating characteristics, a bonding portion of a heat generating body which is provided with the bonding portion bonding to a substrate; and a second cooling section, which cools, with a second refrigerant liquid, a heat generating body portion different from the bonding portion.

Description

Cooling device, electronic device having cooling device, and cooling method of heating element

The present invention relates to a cooling device, an electronic device having a cooling device, and a method for cooling a heating element.

In recent years, as the processing speed of information devices such as servers and computers has improved, the performance of semiconductor devices has been improved. As the performance of semiconductor devices increases, the size of semiconductor elements (chips) used in the semiconductor devices increases and the amount of heat generated during operation also increases. For this reason, development of a technique for efficiently cooling a semiconductor device is underway.

As a technique for cooling a semiconductor device, for example, as shown in FIG. 1A, a jet cooling method in which a pressurized refrigerant liquid 103 is sprayed from a nozzle 105 onto a semiconductor element 121 or a package 120 (see, for example, Patent Documents 1 and 2) is known. ing. For example, as shown in FIG. 1B, an immersion boiling cooling method in which the semiconductor element 121 is immersed in an insulating refrigerant liquid 104 having a low boiling point is known.

In any of the cooling methods, the semiconductor element 121 that is a high heating element can be cooled by utilizing the boiling and vaporization of the

refrigerant liquids

103 and 104. The

refrigerant liquids

103 and 104 are circulated by the pump 108 and radiated by the radiator 106. A fan 107 is used to increase the heat dissipation efficiency.

A technique for forming an air curtain around a chip when performing a jet cooling method has also been proposed (see, for example, Patent Document 3). In this technology, the chip is held downward, the coolant is sprayed from the lower nozzle to the chip, and an air curtain is formed by flowing air from the periphery of the chip in the direction opposite to the coolant spraying direction. This prevents the coolant from flowing into the region other than the cooling surface.

JP-A-5-160313 JP-A-5-136305 Japanese Laid-Open Patent Publication No. 1-025447

However, in the jet cooling method shown in FIG. 1A, since the joint 125 is a place that is responsible for electrical connection, cooling is performed directly using the aqueous coolant 103 from the viewpoint of maintaining insulation between different wirings. Is not preferred. When jet cooling is performed so as to avoid the joint 125, the cooling capacity is limited. In addition, when the semiconductor element 121 generates a large amount of heat, a large amount of boiling bubbles are generated, so that the cooling efficiency of the semiconductor element 121 decreases.

On the other hand, in the immersion boiling cooling system shown in FIG. 1B, the semiconductor element 121 is immersed in the insulating refrigerant liquid 104, so that the joint 125 can be directly cooled. However, since it is preferable that the refrigerant liquid 104 has an insulating property, for example, when a fluorine-based refrigerant liquid such as chlorofluorocarbon is used, there is a problem that an environmental load increases.

The present invention relates to a cooling device, an electronic device having a cooling device, and a method for cooling a heating element capable of efficiently and stably cooling a heating element having a high calorific value such as a semiconductor element while minimizing environmental burden. The issue is to provide.

According to one aspect of the invention, the first cooling section that cools the joint portion of the heat generating body including the joint section with the substrate with the first coolant liquid having insulation properties is different from the joint section of the heat generating body. There is provided a cooling device having a second cooling section that cools the portion with a second refrigerant liquid.

According to another aspect of the invention, a semiconductor device having a junction with a substrate, a first cooling unit that cools the junction of the semiconductor device with a first coolant liquid having insulation, and the semiconductor An electronic apparatus is provided that includes a second cooling unit that cools a portion of the apparatus that is different from the bonding unit with a second refrigerant liquid.

According to another aspect of the invention, the joining portion of the heating element including the joining portion with the substrate is cooled with the first coolant liquid having insulation, and a portion different from the joining portion of the heating element is provided. There is provided a method for cooling a heating element, characterized by cooling with a second refrigerant liquid.

According to the above viewpoint, it is possible to efficiently and stably cool a heating element such as a semiconductor element while minimizing environmental burden.

It is the schematic which shows the cooling device of the conventional jet cooling system. It is the schematic which shows the cooling device of the conventional immersion boiling cooling system. 1 is a schematic diagram of an electronic device having a cooling device of Example 1. FIG. It is the schematic plan view and side view of a board | substrate which mounted the some semiconductor element with the other module. It is the schematic which shows the structure of the cooling device in the case of cooling the board | substrate of FIG. It is the schematic of the experimental model used in order to measure the cooling effect of the cooling device of Example 1. FIG. It is a graph which shows the cooling effect of the cooling device of Example 1 compared with the conventional jet cooling system. It is a table | surface which shows the cooling effect of the cooling device of Example 1 compared with the conventional jet cooling system. 6 is a schematic diagram of a semiconductor device using a cooling device of Example 2. FIG. It is the schematic of the experimental model used in order to measure the cooling effect of the cooling device of Example 2. FIG. It is a graph which shows the cooling effect of the cooling device of Example 2 in comparison with the conventional jet cooling method. It is a table | surface which shows the cooling effect of the cooling device of Example 2 compared with the conventional jet cooling system.

Embodiments of the present invention will be described below with reference to the drawings. In the figure, the same reference numerals are used for components having the same function, and repeated description is omitted. In each embodiment, a configuration for cooling a semiconductor package mounted on a substrate will be described as an example. However, the cooling device of the present invention is suitable for cooling an arbitrary heating element such as an electronic module, and in particular, an external device. Suitable for cooling a heating element having an electrical connection to

In each embodiment, the insulating refrigerant liquid and the aqueous refrigerant liquid are used in two layers separated, and the electrical junction having a large calorific value is directly cooled by the insulating refrigerant liquid and other than the electrical junction. The heating element portion is cooled with an aqueous refrigerant liquid. This enables efficient and stable cooling while minimizing the environmental load. The cooling device by two-layer separation can be applied not only to a horizontal semiconductor device in which semiconductor packages and substrates are horizontally arranged, but also to a vertical semiconductor device in which substrates are arranged vertically in a rack shape.

Therefore, in the first embodiment, a configuration example in which the cooling device is applied to a horizontally arranged semiconductor device will be described, and in the second embodiment, a configuration example in which the cooling device is applied to a vertical arrangement will be shown. Here, the horizontal arrangement refers to an arrangement in which semiconductor devices and substrates are placed in a direction orthogonal to the direction of gravity. Vertical arrangement refers to an arrangement in which semiconductor devices and substrates are placed along the direction of gravity. In the following description, semiconductor elements (chips), semiconductor packages, semiconductor modules and the like to be cooled are collectively referred to as “semiconductor devices”, and a circuit board, a relay board, and a system board on which these semiconductor devices are mounted. May be collectively referred to as “substrate”.

FIG. 2 is a schematic diagram illustrating a configuration example of the electronic device 10 including the cooling device according to the first embodiment. In the first embodiment, the horizontal semiconductor package 20 in which the substrate 30 is disposed horizontally (that is, in a direction orthogonal to the direction of gravity) is cooled.

The semiconductor package 20 is, for example, one in which a semiconductor element 21 is electrically connected to a circuit board or a relay board 22 by solder bumps 23 and is entirely sealed as one package. The semiconductor package 20 has a joint 24 for electrical connection with the outside, and is electrically connected to a substrate 30 such as a printed wiring board via the joint 24. The heat generated in the semiconductor element 21 is conducted to the circuit board (or relay board) 22 through the solder bumps 23 and the like, and is further transferred to the board 30 through the joints 24 and the like. The joint 24 is a part that generates a higher amount of heat than other parts and requires efficient cooling. However, since the joint portion 24 is a portion that is responsible for electrical connection with the substrate, it is not preferable to cool the joint portion 24 with an aqueous refrigerant liquid.

Therefore, the insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 are separated into two layers in the casing 11, and the insulating cooling liquid 14 is used for cooling the surface including the joint portion 24 of the semiconductor package 20, and the other portions. The aqueous refrigerant liquid 13 is used for cooling. Specifically, the insulating refrigerant liquid 14 is arranged so that the semiconductor package 20 and the substrate 30 are disposed inside the airtight casing 11, and the joint 24 and the package side surface of the semiconductor package 20 are immersed in the insulating refrigerant liquid 14. Is enclosed in the casing 11. The casing 11 can be made of metal, resin, ceramics, glass, or the like. In the embodiment, a metal having high thermal conductivity such as aluminum is used. The insulating refrigerant liquid 14 is a fluid that is chemically stable, does not corrode, and has electrical insulation. Refrigerant liquids that satisfy this condition include, for example, fluorinated inert liquids (FC-72, etc.), fluorocarbon refrigerants, alternative CFCs (HFC-365mfc, HFE-7000, etc.), halogenated hydrocarbon refrigerants (pentane, etc.) ), A refrigerant liquid mainly composed of insulating oil such as silicone oil can be used.

On the other hand, the aqueous refrigerant liquid 13 is supplied to a portion different from the joint portion 24 such as the back surface 26 of the semiconductor package 20. The aqueous refrigerant liquid 13 is, for example, water, pure water or the like, and is sprayed from the nozzle 15 located above the semiconductor package 20 to the back surface 26 of the semiconductor package 20. In this case, the specific gravity of the insulating refrigerant liquid 14 is larger than the specific gravity of the aqueous refrigerant liquid 13 (the specific gravity of the insulating refrigerant liquid 14 is 1.68 when FC-72, which is a fluorine-based inert liquid, is used). By utilizing this specific gravity difference, the insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 can be separated into two layers.

The aqueous refrigerant liquid 13 ejected from the nozzle 15 contacts the back surface 26 of the semiconductor package 20 and spreads to the peripheral region of the semiconductor package 20, takes heat of the semiconductor package 20, and moves to the inner wall of the casing 11 on the low temperature side. Spread. At this time, since the insulating refrigerant liquid 14 having a large specific gravity for immersing the side surface of the semiconductor package 20 and the bonding portion 24 exists below, the aqueous refrigerant liquid 13 is prevented from being mixed into the bonding portion 24. The aqueous refrigerant liquid 13 whose temperature has been increased by removing heat from the back surface 26 of the semiconductor package 20 is discharged to the outside of the casing 11 by the pump 18a, and heat exchange is performed by external cooling means, for example, a radiator 16 and a fan 17. Is done. The low-temperature aqueous refrigerant liquid 13 is supplied to the nozzle 15 by the pump 18b. The

pump

18a, 18b, the external cooling means 16, 17, the nozzle 15 and the pipe 19 connecting them constitute a circulation system of the aqueous refrigerant liquid 13. Thereby, the aqueous refrigerant liquid 13 taken out from the casing 11 can be circulated and supplied to a portion different from the joint portion 24.

The insulating refrigerant liquid 14 is vaporized by the heat transmitted to the joint portion 24 of the semiconductor package 20 and becomes vapor. The vapor of the insulating refrigerant liquid 14 dissolves in the aqueous refrigerant liquid 13, but when the temperature of the aqueous refrigerant liquid 13 is lower than the boiling point of the insulating refrigerant liquid 14, the vapor of the insulating refrigerant liquid 14 enters the aqueous refrigerant liquid 13. It contacts and aggregates to form a liquid phase and naturally circulate into the insulating refrigerant liquid 14. For example, when FC-72, which is a fluorine-based inert liquid, is used as the insulating refrigerant liquid 14, the boiling point is 56 ° C. When the aqueous refrigerant liquid 13 is cooled and circulated to maintain the temperature of the aqueous refrigerant liquid 13 in the casing 11 lower than 56 ° C., the insulating refrigerant liquid 14 can be naturally circulated in the casing inside 11. Volatilization of the low boiling point fluorine-based liquid 14 is suppressed by the shield of the aqueous refrigerant liquid 13.

Although not shown, a second circulation system that mechanically circulates the insulating refrigerant liquid 14 may be provided in addition to the circulation system for the aqueous refrigerant liquid 13.

FIG. 2 shows an example in which a single semiconductor package 20 is cooled for simplification. However, the cooling device described above includes a multi-CPU in which a plurality of semiconductor packages 20 and electronic modules are mounted on a system boat 30. It can also be applied to cooling.

FIG. 3 is a top view of the substrate 30 on which the multi-CPU is mounted and a cross-sectional view taken along the line AA ′. On the substrate 30, a plurality of CPUs (semiconductor packages) 20 a, 20 b, 20 c, and 20 d are arranged together with other modules 32. The other modules are, for example, a memory module, a switch, a power module, etc., but are represented by the memory module 32. During operation, heat is generated from each of the semiconductor packages 20a to 20d and the memory module 32. Therefore, when cooling the multi CPU in a horizontal arrangement, it is desirable to supply the aqueous refrigerant liquid 13 by arranging the nozzle 15 for each of the semiconductor packages 20a and 20b and the memory module 32.

FIG. 4 is a schematic diagram showing a configuration of a semiconductor device 40 with a cooling device for cooling the multi CPU. The substrate 30 on which the semiconductor packages 20a and 20b and the memory module 32 are mounted is disposed in a hermetically sealed casing 11. In the casing 11, the insulating refrigerant liquid 14 that immerses the side surfaces of the semiconductor packages 20 a and 20 b and the joint portion 24 and the memory module 32 is enclosed. The

nozzles

15a, 15b, 15c are arranged above the

semiconductor packages

20a, 20b and the memory module 32, and the aqueous refrigerant liquid 13 is directed toward the

back surfaces

26a, 26b, 36 of the corresponding semiconductor devices (modules) 20a, 20b, 32. Be injected. On the other hand, the joint portions 24 of the semiconductor packages 20a and 20b that generate a large amount of heat and the joint portion (not shown) to the substrate 30 of the memory module 32 are immersed in the insulating coolant 14 and directly cooled. The aqueous refrigerant liquid 13 is circulated through a pipe 19 connecting the

pumps

18a and 18b and the cooling means 16 and 17, and the aqueous refrigerant liquid 13 having a low temperature is supplied to the nozzles 15a to 15c.

3 and 4, the same size semiconductor packages 20a to 20d are arranged on the substrate 30. However, when different size semiconductor packages are arranged, cooling can be performed in the same manner. Also, a configuration may be adopted in which one nozzle 15 is provided for a plurality of semiconductor packages 20 by controlling the jetting direction of the nozzles 15 shown in FIG.

As described above, in the first embodiment, the insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 are separated into two layers by using the difference in specific gravity, and the junction 24 of the semiconductor package 20 is immersed and cooled by the insulating refrigerant liquid 14. At the same time, the aqueous refrigerant liquid 13 performs jet cooling on a portion different from the joint portion 24, such as the package back surface (surface opposite to the joint portion) 26. Since the semiconductor package 20 is cooled from the entire periphery with the main cooling means being water-cooled while ensuring the insulation with respect to the joint portion 24 responsible for electrical connection, the environmental load is minimized, and the semiconductor element 21 and the semiconductor package 20 Can be efficiently and stably cooled. Moreover, in Example 1, since the whole semiconductor package 20 is immersed, it does not touch external air. Therefore, there is no risk of condensation and migration of the joint can be prevented.

FIG. 5 is a schematic diagram of an experimental model used to measure the effect of Example 1. As a cooling target, a CPU (CORE 2 QUAD 3 GHz) 20a manufactured by INTEL and peripheral parts 32 were used. FC-72, which is a fluorine-based inert liquid, was used as the insulating refrigerant liquid 14 and water was used as the aqueous refrigerant liquid 13 to cool by two-layer separation. The joint portion 24 of the CPU 20a is immersed in the insulating refrigerant liquid 14 having a high specific gravity. The aqueous refrigerant liquid 13 having a lower specific gravity was circulated by the pump 18 at a flow rate of 3 liters / minute, heat was exchanged by the radiator 16 at a heat release amount of 80 W · h, and then supplied to the nozzle 15. The temperature of the CPU 20 was measured when the CPU usage rate was 100%. The measured temperature of the CPU 20 was the monitoring temperature inside the CPU. As a comparative example, the same CPU 20 and peripheral part 32 were used, and the CPU temperature when the CPU usage rate was 100% was measured in the same manner by the jet cooling method using only the aqueous refrigerant liquid 13 as shown in FIG. 1A.

FIG. 6A is a graph showing actual measurement results, and FIG. 6B is a table comparing the CPU temperature and calorific value conversion of the experimental model of Example 1 and the conventional model by averaging the actual measurement results of FIG. 6A. As shown in FIGS. 6A and 6B, in the conventional model of FIG. 1A, the CPU core temperature exceeds 60 ° C. several minutes after the CPU usage rate reaches 100%, and the average CPU temperature under cooling is 61 ° C. On the other hand, in the experimental model of Example 1, the average CPU temperature when the CPU usage rate is 100% is 53 ° C. In terms of calorific value, the conventional model is 180 W, and the experimental model of Example 1 is 140 W. Thus, with the configuration of Example 1, it is possible to achieve a 40 W reduction in terms of calorific value and an 8 ° C. reduction in average CPU temperature. In the actual measurement graph of FIG. 6A, a slight amplitude is seen in the CPU core temperature. This is due to the influence of the operation of the CPU, and the stability of the cooling function is ensured. The cooling function can be further improved by controlling the radiator heat radiation amount, the pump flow rate, the nozzle arrangement, the jet direction, and the like.

FIG. 7 is a schematic diagram illustrating a configuration example of an electronic device 70 including the cooling device according to the second embodiment. In the second embodiment, the vertical semiconductor package 20 in which the substrate 30 is arranged vertically (that is, along the direction of gravity) is cooled. The configuration of the semiconductor package 20 and the bonding configuration to the substrate 30 are the same as those in the first embodiment, and a description thereof will be omitted.

Also in the second embodiment, as in the first embodiment, the joint portion 24 of the semiconductor package 20 is directly cooled by the insulating refrigerant liquid 14, and the back surface (surface opposite to the joint portion 24) 26 of the semiconductor package, etc. A portion different from the joint portion 24 is cooled by the aqueous refrigerant liquid 13. In order to realize this configuration in the vertical arrangement, in the second embodiment, the first nozzle 75 is arranged above the substrate 30 on which the semiconductor package 20 is mounted, and the insulating refrigerant liquid 14 is supplied from the upper end side of the substrate 30. Supply toward the joint 24. On the other hand, the second nozzle 15 is disposed on the side of the vertically standing semiconductor package 20 to supply the aqueous coolant 13 toward the back surface 26 of the semiconductor package.

The first nozzle 75 forms the curtain flow 76 so that the end face of the semiconductor package 20 and the entire joint portion 24 are covered with the insulating refrigerant liquid 14. Insulating refrigerant 14 is a fluid that is chemically stable, non-corrosive, and has electrical insulation, as in Example 1. For example, insulation such as fluorinated inert liquids (FC-72, etc.), fluorocarbon refrigerants, alternative CFCs (HFC-365mfc, HFE-7000, etc.), halogenated hydrocarbon refrigerants (pentane, etc.), silicone oil, etc. A refrigerant liquid mainly composed of oil can be used.

The second nozzle 15 injects the aqueous refrigerant liquid 13 to a portion different from the bonding portion 24 such as a surface (back surface) 26 opposite to the bonding portion 24 of the semiconductor package 20. At this time, since the joint portion 24 is covered with the curtain flow 76 of the insulating refrigerant liquid 14, the aqueous refrigerant liquid 13 can be prevented from entering the joint portion 24. Thus, the insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 are separated into two layers in the direction of gravity.

The insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 whose temperature has increased due to heat exchange with the semiconductor package 20 are accumulated at the bottom of the casing 11. When the fluorine-based inert liquid FC-72 is used as the insulating refrigerant liquid 14, the specific gravity is larger than the specific gravity of the aqueous refrigerant liquid 13. However, since the insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 flow down from above to the bottom of the casing 11, they are partially mixed at the bottom of the casing 11.

The insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 that have reached a high temperature are discharged from the bottom of the casing 11 through the first pipe 19 a and are heat-exchanged by the radiator 16 and the fan 17. The refrigerant liquid that has undergone heat exchange and has reached a low temperature is sent to the refrigerant liquid separation tank 79. In the refrigerant liquid separation tank 79, the insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 are separated into two layers by the difference in specific gravity. Of the separated refrigerant liquid, the insulating refrigerant liquid 14 is supplied to the first nozzle 75 via the pump 78a and the second pipe 19b. The aqueous refrigerant liquid 13 is supplied to the second nozzle 15 via the pump 78b and the third pipe 19c. As described above, the two-layer separation of the refrigerant liquid can be utilized to circulate the aqueous refrigerant liquid 13 and the insulating refrigerant liquid 14 that have become low temperature to the corresponding

nozzles

15 and 75, respectively. As a result, the semiconductor package 20 can be cooled efficiently and stably even in the vertical arrangement. In addition, you may provide a pump in the 1st piping 19a as needed.

The configuration of the second embodiment can also be applied when the multi-CPU board 30 of FIG. 3 is arranged vertically. In this case, the nozzles 75 for forming the curtain flow 76 are preferably provided for each row of the semiconductor packages 20 arranged in the direction of gravity on the substrate 30. Alternatively, the number of nozzles 75 can be set as appropriate in accordance with the size, shape, and configuration of the opening of the nozzle, the flow rate of the insulating refrigerant liquid 14 to be jetted, the size of the substrate 30, and the like.

FIG. 8 is a schematic diagram of an experimental model used to measure the effect of Example 2. As a cooling target, a CPU (CORE 2 QUAD 3 GHz) 20 and peripheral parts 32 manufactured by INTEL were used. FC-72, which is a fluorine-based inert liquid, was used as the insulating refrigerant liquid 14, water was used as the aqueous refrigerant liquid 13, and cooling was performed by two-layer separation in the direction of gravity. The insulating refrigerant liquid 14 and the aqueous refrigerant liquid 13 were discharged from the bottom of the casing 11, and heat was exchanged by the radiator 16 at a heat release amount of 80 W · h, and then two layers were separated in the horizontal direction by the refrigerant liquid separation tank 79. The insulating refrigerant liquid was supplied to the nozzle 715 by the pump 78a, and the aqueous refrigerant liquid was supplied to the nozzle 15 by the pump 78b. The temperature of the CPU 20 was measured when the CPU usage rate was 100%. The measured temperature of the CPU 20 was the monitoring temperature inside the CPU. As a comparative example, the same CPU 20 and peripheral part 32 were used, and the CPU temperature when the CPU usage rate was 100% was measured in the same manner by the jet cooling method using only the aqueous refrigerant liquid 13 as shown in FIG. 1A.

FIG. 9A is a graph showing actual measurement results, and FIG. 9B is a table comparing the CPU temperature and calorific value conversion of the experimental model of Example 2 and the conventional model by averaging the actual measurement results of FIG. 9A. As shown in FIGS. 9A and 9B, in the conventional model of FIG. 1A, the CPU core temperature exceeds 60 ° C. several minutes after the CPU usage rate reaches 100%, and the average CPU temperature under cooling is 61 ° C. On the other hand, in the experimental model of Example 2, the average CPU temperature when the CPU usage rate is 100% is 49 ° C. In terms of calorific value, the conventional model is 180 W, and the experimental model of Example 1 is 120 W. Thus, in the configuration of the first embodiment, a reduction of 60 W in terms of calorific value and a reduction of 12 ° C. in the average CPU temperature can be achieved.

The configuration of the second embodiment has higher cooling efficiency than that of the first embodiment and can realize stable cooling. This is because the insulating refrigerant liquid 14 is supplied as a curtain flow to the joint portion 24 (see FIG. 7) of the semiconductor package 20. High cooling efficiency can be obtained by supplying and cooling the insulating refrigerant liquid 14 that is always kept at a low temperature to the joint portion 24 that generates a large amount of heat.

Thus, according to the present invention, for example, the following effects can be obtained.
(1) High-efficiency cooling: Direct cooling of the entire circumference of the semiconductor device is realized by water cooling by using a jet cooling with an aqueous coolant and a cooling of the joint with an insulating coolant.
(2) Large area cooling: The entire system board including the memory, switch, power module, etc. can be integrally cooled.
(3) Low environmental load: Highly efficient cooling can be realized while reducing the load on the environment by minimizing the amount of fluorine-based refrigerant and water cooling the main cooling means.
(4) High reliability: Since the substrate does not come into contact with outside air, it is possible to prevent condensation due to a temperature difference and to prevent migration.
(5) Cost reduction: Since it is possible to cool together, it is not necessary to provide a thermal module for each CPU. In addition, it is possible to reduce the number of parts and power consumption, such as eliminating the need for a heater for preventing condensation.

¡It can be used for cooling of heating elements and electronic equipment with cooling equipment. It can also be applied to a rack in which a large number of system boards are arranged vertically and a stack structure in which multiple system boards are stacked.

10, 40, 70 Semiconductor device 11 Casing (housing)
13 Aqueous refrigerant liquid 14 Insulating

refrigerant liquid

15, 15a, 15b, 75 Nozzle (refrigerant liquid supply means)
18a, 18b, 78a, 78b Pump 19 Pipe 19a First pipe 19b Second pipe 19c

Third pipe

20, 20a, 20b Semiconductor package (semiconductor module)
21 Semiconductor element 24 Junction 30 Substrate 76 Curtain flow 79 Refrigerant liquid separation tank

Claims

A first cooling section that cools the joint section of the heating element including the joint section with the substrate with a first coolant liquid having insulation;
A second cooling section that cools a portion of the heating element that is different from the joining section with a second refrigerant liquid;
A cooling device characterized by comprising:
The first cooling unit immerses the joint in the first refrigerant liquid,
The cooling device according to claim 1, wherein the second cooling unit supplies the second refrigerant liquid to a portion different from the joint.
The specific gravity of the first refrigerant liquid is greater than the specific gravity of the second refrigerant liquid,
The cooling device further includes a casing for storing the first refrigerant liquid and the second refrigerant liquid,
The cooling device according to claim 2, wherein the second cooling unit includes a first supply unit that supplies the second refrigerant liquid taken out from the casing to a portion different from the joint.
A circulation part for circulating the second refrigerant liquid that has cooled the heating element;
A heat dissipating part which is provided in the middle of the circulation part and dissipates heat from the second refrigerant liquid;
Further comprising
4. The cooling device according to claim 3, wherein the circulation unit supplies the second refrigerant liquid after heat dissipation to the first supply unit. 5.
The first cooling unit supplies the first refrigerant liquid to the joint,
The cooling device according to claim 1, wherein the second cooling unit supplies the second refrigerant liquid to a portion different from the joint.
The specific gravity of the first refrigerant liquid is greater than the specific gravity of the second refrigerant liquid,
The cooling device further includes an accommodating portion for storing the first refrigerant liquid and the second refrigerant liquid,
The first cooling unit includes a second supply unit that supplies the first refrigerant liquid taken out from the storage unit to the joint unit,
The cooling device according to claim 5, wherein the second cooling unit includes a third supply unit that supplies the second refrigerant liquid taken out from the storage unit to a portion different from the joint unit. .
The cooling device according to claim 5, wherein the second supply unit forms a curtain flow that covers the joint with the first refrigerant liquid.
A first pipe for supplying the first refrigerant liquid and the second refrigerant liquid supplied to the heating element to the storage unit;
Means for connecting the first refrigerant and separating the insulating refrigerant liquid and the aqueous refrigerant liquid;
A second pipe for supplying the first refrigerant liquid from the storage unit to the second supply unit;
A third pipe for supplying the second refrigerant liquid from the storage unit to the third supply unit;
The cooling device according to claim 5, further comprising:
The cooling device according to any one of claims 1 to 8, wherein the first refrigerant liquid contains one of fluorocarbon, halogenated hydrocarbon, and insulating oil.
The cooling device according to any one of claims 1 to 8, wherein the second refrigerant liquid contains water or pure water as a main component.
A semiconductor device comprising a junction with the substrate;
A first cooling section that cools the joint portion of the semiconductor device with a first coolant liquid having insulation;
A second cooling section that cools a portion of the semiconductor device that is different from the bonding section with a second refrigerant liquid;
An electronic device comprising:
The first cooling unit immerses the joint in the first refrigerant liquid,
The electronic device according to claim 11, wherein the second cooling unit supplies the second refrigerant liquid to a portion different from the joint.
The specific gravity of the first refrigerant liquid is greater than the specific gravity of the second refrigerant liquid,
The cooling device further includes a casing for storing the first refrigerant liquid and the second refrigerant liquid,
The electronic device according to claim 12, wherein the second cooling unit includes a first supply unit that supplies the second refrigerant liquid taken out from the casing to a portion different from the joint unit.
A circulation unit for circulating the second refrigerant liquid that has cooled the semiconductor device;
A heat dissipating part which is provided in the middle of the circulation part and dissipates heat from the second refrigerant liquid;
Further comprising
The electronic device according to claim 13, wherein the circulation unit supplies the second refrigerant liquid after heat dissipation to the first supply unit.
The first cooling unit supplies the first refrigerant liquid to the joint,
The electronic device according to claim 11, wherein the second cooling unit supplies the second refrigerant liquid to a portion different from the joint.
The specific gravity of the first refrigerant liquid is greater than the specific gravity of the second refrigerant liquid,
The cooling device further includes an accommodating portion for storing the first refrigerant liquid and the second refrigerant liquid,
The first cooling unit includes a second supply unit that supplies the first refrigerant liquid taken out from the storage unit to the joint unit,
The electronic device according to claim 14, wherein the second cooling unit includes a third supply unit that supplies the second refrigerant liquid taken out from the storage unit to a portion different from the joint unit. .
16. The electronic apparatus according to claim 15, wherein the second supply unit forms a curtain flow that covers the joint with the first refrigerant liquid.
A first pipe for supplying the first refrigerant liquid and the second refrigerant liquid supplied to the heating element to the storage unit;
A second pipe for supplying the first refrigerant liquid from the storage unit to the second supply means;
A third pipe for supplying the second refrigerant liquid from the storage unit to the third supply means;
The electronic device according to claim 15, further comprising:
The electronic device according to any one of claims 11 to 18, wherein the first refrigerant liquid contains any of fluorocarbon, halogenated hydrocarbon, and insulating oil.
Cooling the joining portion of the heating element having a joining portion with the substrate with a first coolant liquid having insulation properties, and cooling a portion different from the joining portion of the heating body with a second coolant liquid. A method for cooling a heating element.