JPS60253248A - Heat conductive cooling module device - Google Patents

Abstract

PURPOSE:To prevent or reduce the fatigue failure of a heat conductive path by a method wherein the heat conductive path to be provided between a cooling means and the heat generating device to be cooled is constituted by a part consisting of a sintered body having silicon carbide as a main ingredient and another part consisting of a low melting point metal, thereby enabling to obtain an excellent cooling efficiency. CONSTITUTION:A heat conductive pad 20 consisting of a low melting point metal, which is metallically coupled to the chip 10 and the housing 16, is provided between each chip 10 and each part of the housing 16 opposing to the chip 10, and said pad 20 constitutes the heat conductive path ranging from the chip 10 to the housing 16. A silicon carbide sintered body is selected as the material of the housing 16, and an eapecially excellent efficiency is displayed when alumina ceramic is used as the base material of a substrate 12 and silicon is used as the material of the chip 10. To be more precise, the silicon carbide sintered body has the thermal expansion coefficient extremely approximate to that of silicon, and the thermal fatigue failure of a heat conductive pad 20 can be prevented. Also, the thermal fatigue failure of the sealing member 17 located between the substrate 12 and the housing 16 can be prevented.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a structure for transmitting heat generated by a semiconductor device substrate to a cooling device, and specifically, a structure in which the semiconductor device substrate is attached to a wiring board with a minute solder. The present invention relates to a thermal conduction cooling module apparatus for cooling semiconductor device substrates in integrated circuit package assemblies including single device substrates or multiple device substrates.

[Background of the invention]

Large-scale Kameko computers are required to have high calculation speeds, so in recent years semiconductors have been developed in which a large number of semiconductor elements are integrated into a limited semiconductor substrate, thereby shortening the length of electrical interconnections between each element as much as possible. Apparatus, namely I, arge 5cale
Integrated C1rcuit (hereinafter referred to as LSI)
) chips are being developed. Furthermore, the circuit board on which the LSI chip is mounted and which electrically relays and connects the chip and external circuits is also electrically wired in multiple layers and with high density, thereby substantially shortening the length of the relay connection wiring. Furthermore, L.S.
A method has been developed in which a large number of I-chips are mounted on a circuit board. In order to maintain the operating parameters of the LSI chip within a predetermined range and to prevent the LSI chip from being destroyed due to overheating, it is necessary to provide auxiliary means to efficiently dissipate the heat generated by the operation to the outside.

When the packaging density of LSI chips is low and the amount of heat generated is small, conventionally a method has been adopted in which a heat radiator connected from the LSI chip as a heat generation source via a heat relay medium is cooled by forced convection using air. Ta. However, LSI
As the packaging density of chips increases and the amount of heat generated increases, it is necessary to further strengthen the cooling of the heat sink, and this requires increasing the air velocity, which not only has its limits. As a result, new noise problems arise.

Therefore, unless an auxiliary cooling means, such as an alternative to this forced air cooling method, is provided, it is not possible to maintain the LSI chip within an appropriate operating temperature range.

One example of auxiliary cooling means that has been proposed is a cooling system that uses both air cooling and liquid cooling. this is,
As shown in U.S. Pat. No. 3,741,292,
This is a module in which a heat-generating component is immersed in a portion surrounded by a low-melting-point dielectric liquid enclosed within a capsule. The liquid often used for this purpose is a fluorocarbon liquid with a low boiling point, which boils at a relatively low temperature. In this cooling system, the heat-generating component or the dielectric liquid into which the heat is transferred is converted into vapor and moves from the liquid level to the vapor part located above the liquid level.
It is cooled by internal fins that act as condensers extending from the container to the inside, and the cycle is repeated until it is liquefied again. At this time, the external fins extending outward from the container are air-cooled and serve as a heat radiator for the heat transferred from the internal fins.

Through the above process, heat dissipation of the heat generating component is achieved.

However, this type of liquid encapsulation module must be maintained to ensure that the basic process of boiling-condensation is carried out reliably, and for this purpose extremely pure and contaminant-free liquid as a coolant must be maintained. I need. However, this cooling concept cannot be easily applied when cooling heat-generating components such as LSI chips. This is because there is an extremely high risk that the LSI chip constituent materials will be corroded by the liquid and impurities or contaminants incorporated into the liquid, and that failures will occur as a result.

U.S. Pat. No. 3,993,123 discloses a cooling module arrangement in which a heat generating device, such as one or more semiconductor chips to be cooled, is encapsulated with a gas. The heat generating device is mounted on an alumina substrate and hermetically sealed between the substrate and the cap, and this sealed space is filled with an inert gas. The wall of the cap facing the substrate is provided with an elongated aperture extending toward the heat generating device. An elastic member is placed at the bottom of the aperture. Each hole has an LSI at one end.
A thermally conductive member provided opposite the chip is guided and a narrow gap is formed between the wall of each aperture and the thermally conductive member. The elastic member applies a force to the thermally conductive member that presses the thermally conductive member against the heat generating device. The airtight space is filled with an inert gas, and this inert gas fills the gap between the υ opening and the thermally conductive member and the interface between the heat generating device and the thermally conductive member. The heat generated by the heat generating component reaches the cap via the inert gas and the thermally conductive member, and is emitted to the heat sink coupled to the cap.

In the above-mentioned encapsulated cooling module device, copper or aluminum is used as the cap material and the thermally conductive member, and helium, hydrogen, or carbon dioxide is used as the filler gas. These materials have excellent thermal conductivity, and by constructing the heat conduction path from the heat generating device to the heat sink with these materials, efficient heat dissipation is realized. However, such an encapsulated cooling module device occupies a large area, making it difficult to increase the density when mounting the module device on a printed circuit board. In order to form a highly airtight space, a flange is provided in the part that forms the sealing part with the cap, and extends from the periphery of the alumina plate toward the sealing part. This is because a fastening means for crimping the cap and the flange is provided to form the part. or,
A force field stand in which the cap is made of copper, which has good thermal conductivity, increases the weight of the module device and accelerates the deterioration of the connection part that communicates the input/output signals of the module with other circuits.

Furthermore, heat generating devices are mounted on the substrate within the encapsulation capsule as densely as possible. Each heat generating device has a large number of semiconductor elements integrated in a limited semiconductor substrate. In order for each semiconductor element to form an electric circuit, the elements must be electrically insulated from each other as necessary.

For this reason, semiconductor elements are generally formed in semiconductor regions called islands, which are electrically isolated by pn junctions. The problem is that a voltage sufficient to reverse bias the pn junction is applied to the semiconductor substrate, ie, the heat generating device substrate that forms a contact interface with the thermally conductive member. It is rare that all of the heat generating devices mounted on a board are made of semiconductor substrates having the same function, and in general, when two or more types of heat generating devices with different functions are mounted in the same cooling module device. I have to think about it. In such cases, it is necessary to maintain the reverse bias voltage at a level of 2 or more. By the way, heat generating devices given different reverse bias voltages must be electrically connected to each other via an electrically conductive thermally conductive member, an elastic member, or a cap. Conditions cannot be maintained and the circuit function of the entire cooling module device is impaired. Further, if the reverse bias conditions of all the heat generating devices mounted in the cooling module device are exactly the same, the above-mentioned problem (9) is solved. However, due to power, the cooling module devices are electrically connected to each other through impurities and contaminants in the heat sink or refrigerant that connects to the cap to form a contact interface, and furthermore, cooling on the printed circuit board that is densely mounted in the housing. There is a risk of forming electrical short circuit networks due to vibrating contact between module devices. Therefore, it is undesirable for heat generating devices mounted on a board to be electrically connected to each other other than through a pre-planned conductive path. must be given.

On the other hand, U.S. Patent Nos. 4,034,468 and 4,081,825
No. 2003-130000, a thermally conductive pad made of a low melting point solder forming a immersed heat transport path is provided between one or more semiconductor chips as a heat generating device to be cooled and a can or cover of a package as a heat sink. A thermally conductive cooling circuit package is disclosed. A semiconductor chip is mounted on an alumina substrate, and the substrate is sealed with a can or cover made of copper or brass. A gap is formed between the semiconductor chip and the can or cover, and a thermally conductive pad made of indium or an alloy thereof is arranged to fill this gap. This thermally conductive pad is metallically bonded to only one of the semiconductor chip, the can, and the cover, and the other engaging portion that is not metallically bonded is non-metallic, such as simply forming a contact interface. is joined to. At this time, in order to realize metallic bonding, a thin film made of chromium-copper-gold, chromium-nickel, titanium-palladium-gold, or chromium-copper is formed on the semiconductor chip or the can or cover. In this heat conduction cooling circuit package, since no mechanical restraint is applied at the contact interface where no metal bonding is made, deterioration due to addition of thermal cycles, such as failure such as fatigue fracture, is less likely to occur. However, it is clear that non-metallic joints that form heat conduction paths are inferior in terms of heat conduction performance compared to interfaces formed by metallic joints.

Furthermore, even in this case, it is natural that it is necessary to provide electrical insulation as described in (11) above in the heat conduction path from the semiconductor chip to the can or cover.

As for this, in U.S. Pat. No. 4,034,468,
It is disclosed that a can or cover made of aluminum oxide, which is itself a good insulator, can be used. However, beryllium oxide has toxicity problems.

Therefore, in order to form a heat conduction path with high cooling efficiency,
Preferably, the heat conduction path from the semiconductor chip as a heat generating device to the housing which is engaged to the heat sink is provided with heat conduction pads which are metallically bonded to both the semiconductor chip and the housing. However, in this case, the thermally conductive pad has a portion that is not metallically bonded to either the semiconductor chip or the housing. A new problem arises that is less likely to occur in conduction cooled packages. In other words, if a thermally conductive pad such as an alloy material is metallically bonded to both a semiconductor chip and a housing member that have different coefficients of thermal expansion, thermal expansion will occur when thermal changes occur due to circuit operation and shutdown. Thermal stress is applied to the thermally conductive pad due to the difference in coefficients, and this thermal stress (12) is applied in return, causing fatigue failure of the thermally conductive pad.
For example, cracks may occur. Such fatigue failure of the heat conduction pad becomes a factor that increases the thermal resistance of the heat conduction path, and in particular, in the case of a heat conduction path associated with a semiconductor chip that generates a large amount of heat, measures must be taken to prevent the failure.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an improved heat conduction cooling module device that efficiently cools a heat generating device to be cooled.

Another object of the present invention is to provide an improved thermal conduction cooling module arrangement that prevents or reduces fatigue failure of the thermal conductive paths.

[Summary of the invention]

The heat conduction cooling module device of the present invention has the following features in order to achieve the above object.

The heat conduction path between the cooling means provided outside the container that seals the heat generating device and the heat generating device to be cooled is formed by a portion made of a sintered body mainly composed of silicon carbide and a portion made of a low melting point metal. The feature (13) is that . The sintered body containing silicon carbide as a main component preferably contains at least one of beryllium, beryllium oxide, and boron nitride.

Since the cap member of the container in the present invention is used as a heat conduction path related to a heat generating device, it is necessary that it has essentially high thermal conductivity, as well as being lightweight and electrically insulating. Preferably. More preferably, the cap member of the container should have a coefficient of thermal expansion similar to that of the heat generating device and the wiring board on which the heat generating device is mounted, and should have high airtightness. This is to avoid fatigue deterioration of the low melting point metal that serves as a heat conduction path and to maintain high airtightness within the container. Therefore, as a result of searching for and comparing materials with such performance, we found that high-density sintered silicon carbide containing at least one of beryllium oxide, beryllium oxide, and boron nitride has the above performance. confirmed.

Specifically, sintered silicon carbide with a beryllium content (in terms of helium oxide) and a boron nitride content of 2 parts by weight or more per 100 parts by weight of silicon carbide has a thermal conductivity of o and 7cn.
t7 (14) C-sub・S (room temperature), density 3.2g/cm", Vickers hardness approximately 4000, bending strength, three-point support) 45 to 9f/
It was noted that the material had suitable performance as a thermally conductive member and a material for a cap member of a container, with a thermal expansion coefficient of 3.7×10 −′/c and an electrical resistivity of 10 13 Ω·m or more (room temperature).

Thermal conductive members and container cap members made of silicon carbide sintered bodies are made of beryllium, beryllium oxide, and boron nitride, which increases the electrical resistance of silicon carbide and elementary grain boundaries, and improves the electrical insulation properties of silicon carbide sintered bodies. At the same time, it is provided with thermal conductivity.

Sintered silicon carbide contains residual silicon, aluminum, iron, titanium, and nickel, or their oxides, carbides, and free carbon, which are contained in the form of impurities in the starting materials. Among these impurities, aluminum has the function of lowering the resistivity of the silicon carbide sintered body, so it is desirable that the amount of aluminum is small. However, on the other hand, aluminum also plays an important role in increasing the density of sintered silicon carbide, that is, reducing the porosity. This porosity (1
The need to reduce 5) has a significant meaning that cannot be ignored in making the package highly airtight, which will be described later. Therefore, in such a case,
It is desirable to add 1,11 J of the above-mentioned beryllium, beryllium oxide, and boron nitride in an amount that offsets the resistivity lowered by the presence of aluminum.

In the thermally conductive cooling module device of the present invention, the resistivity required for the thermally conductive member and the cap member of the container is 101.
0 Ωm or more, and the thermal conductivity is preferably at least equal to or higher than that of aluminum (0.53d/CrrI-C@S). In order to achieve this, the desired amount of addition is 2 parts by weight or more when beryllium is added using beryllium oxide and the amount of boron nitride is added to 100 parts by weight of silicon carbide, which is the main component.

In particular, the cap member forms a space surrounding the heat generating device together with the substrate and other members, and seals in a gas such as helium gas that assists heat transfer at the interface between the heat conducting member and the cap member or the heat generating device. Since it also serves as a container, it must be highly airtight (16). This is because helium gas is a gas with a small atomic radius and easily dissipates through extremely small gaps and pores. Such an airtightness problem must be solved especially when a ceramic material is used as the material for the cap member, unlike when metal is used as the material for the cap member.

This airtightness is equivalent to 10" in terms of helium gas leakage.
-tBtmml/S or less is a preferable value, but in order to impart this degree of airtightness to sintered silicon carbide, it is desirable that the relative density of the sintered body is 97 or more. To obtain such a silicon carbide sintered body, the particle size is typically 2 μm.
The following silicon carbide powders were uniformly mixed with additives that impart insulation and thermal conductivity of equivalent particle size, and the mixture was
After temporary molding at a pressure of about 8MPa, temperature 2050c pressure 3
0MPa-t' Vacuum hot press for about 1 hour (vacuum degree 1
0"' MPa). In this case, in addition to the additives for imparting insulation and thermal conductivity to the sintered silicon carbide, silicon as an impurity contained in the starting raw material,
Aluminum, ridge, titanium, nickel alone (1
7) contains these oxides, carbides and free carbon. These impurities have an effective function to make the silicon carbide crystal grains denser. therefore,
In order to actively impart airtightness to sintered silicon carbide, it is preferable to add silicon, aluminum, iron, titanium, nickel alone or their oxides or carbides.

[Embodiments of the invention]

FIG. 1 is a schematic overhead view showing a heat generating device shown as an LSI chip 10 and a gas-filled heat conduction cooling module device having an auxiliary cooling means for cooling the heat generating device;
FIG. 2 is a sectional view taken along line AA' in FIG. 1. To explain with reference to both figures, about 100 LSI chips 10 each having a solid-state circuit formed on a silicon substrate are connected to micro solder poles on one side of a ceramic multilayer wiring board 12 with an area of about 90 mm x 90 mm. It is attached by 11. The substrate 12 has about 1,500 connecting pins 14 protruding from other sides. These pins 14 (18) are inserted into a wiring board 13 carrying auxiliary circuits, etc., and the heat conduction module device is supported. A protrusion 16 is provided on the side of the substrate 12 on which the chip 10 is mounted, so as to face the peripheral edge thereof.
A concave cap or housing 16 provided with a mark a is mounted thereon, and is hermetically fixed with a sealing member 17 such as a soldering material. A sealed space 19 is formed by these members, that is, the substrate, the housing, and the sealing member, and this space 19 is filled with a thermally conductive gas 3 such as helium gas.
1 (see Figure 2). A thermally conductive pad 20 made of a low melting point metal and metallically bonded to the chip 10 and the housing 16 is provided between each chip 10 and each part of the housing 16 facing it. It forms a heat conduction path. As the material of the housing 16, a silicon carbide sintered body having the above-mentioned performance is selected, but when the base material of the substrate 12 is alumina ceramic or mullite ceramic and the chip 10 is silicon, it exhibits particularly excellent performance. be able to. That is, the silicon carbide sintered body (19) has a coefficient of thermal expansion very similar to that of silicon, and thermal fatigue failure of the thermally conductive pad 20 can be prevented. Furthermore, the silicon carbide sintered body has a coefficient of thermal expansion similar to that of alumina ceramic and mullite ceramic, and the substrate 12
Thermal fatigue failure of the sealing member 17 between the housing 16 and the housing 16 can be prevented. Since the thermally conductive pad 20 is not destroyed, the heat transfer performance of the main thermal conduction path is maintained, and the sealing member 1
7 does not occur, there is no leakage of the thermally conductive gas 31, and the heat transfer performance of the heat conduction path passing through the gas is maintained. However, even when the base material of the substrate 12 is resin, a silicon carbide sintered body can be used for the housing as long as the substrate has an adjusted coefficient of thermal expansion.

In this embodiment, the thermally conductive pad 20 is metallically bonded to the chip 10 and the housing 16 using 67% by weight bismuth-16% by weight lead-17% by weight tin solder. The thermally conductive pad 20 is made of a low melting point metal with a solidus point of 95C and a liquidus point of 149C, and has excellent resistance to fatigue of the thermally conductive pad 20 due to the minute difference in coefficient of thermal expansion between the chip 10 and the housing 16 (20). This is complemented by its plastic deformation performance. In addition to the solder material having the above composition, the thermally conductive pad 20 is made of bismuth, tin,
By using a single metal such as indium or mercury or an alloy material containing at least one of lead, tin, bismuth, indium, cadmium, mercury, and antimony, the same thermal fatigue resistance as described above is imparted.

As is well known, helium gas as the thermally conductive gas 31 is
It is a low molecular weight gas that easily penetrates and fills minute gaps.
It is a good thermal conductor with low thermal resistance, is an inert gas, has high safety, is non-corrosive and non-toxic, and can be the most preferred gas material for encapsulation. However, if there is sufficient heat dissipation capacity to maintain stable operation of the chip 100, gases such as hydrogen, carbon dioxide, and nitrogen may be sealed, or a mixture of two or more of the above gases including helium gas may be sealed. It is also possible to do so. In this case, the type of gas and the gas mixture composition should be appropriately selected based on the balance between the amount of heat generated by the chip 10 to be cooled and the heat dissipation capacity of the entire heat conduction cooling module device (21).

The space 19 is kept airtight by the substrate 12, the housing 16, and the sealing member 17 that fixes these members, thereby preventing the dissipation of the sealed helium gas 31 and protecting it from corrosion caused by the intrusion of outside air. It has become. Tin, lead, germanium,
A gold thread alloy material containing at least one selected from silicon, antimony, bismuth, cadmium, and gallium;
tin, lead, silver, antimony, indium, bismuth, copper,
A brazing material such as lead, tin, or silver alloy containing at least one selected from zinc, gold, and cadmium is preferable. Also,
In addition to fixing means using metal brazing material, thermosetting resin composition,
It is also possible to apply a sealant made of a thermoplastic resin composition.

In this case, since resin compositions are generally inferior in airtightness to gases compared to metals, it is necessary to select the gas to be enclosed. Further, sealing can also be achieved by methods (22) such as pressure bonding, anodic bonding, etc., other than fixing means using metal brazing materials and resin compositions. However, the chips 10 are mounted as densely as possible on the substrate 12, and if a failure occurs in some of them, it becomes impossible to maintain a predetermined circuit function. In such a case, it is necessary to attempt regeneration by either replacing the entire configuration of the heat conduction cooling module device or replacing a part of the chip 10. The latter method can be said to be preferable in that it causes less economic loss than the former. However, for this purpose, the sealing part must be opened and the chip 10
In other words, the thermal conduction cooling module device must be able to be opened, and furthermore, the heat treatment for opening and resealing will not adversely affect other connections, such as the minute solder balls 11. Care must be taken to ensure that this does not affect the From this point of view, the sealing member 1
If 7 is selected, for example, when 95 lead-5 tin based solder is used as the material for the minute solder balls 11, a brazing material having a melting point lower than the solidus point of the solder ball, that is, 95 tin-5 silver, is selected. , 63 tin-37 lead, (23) 80 indium-15 lead-5 silver, 50 tin-50 indium, 34 tin-20 lead-46 bismuth, 14 tin-29 lead-
A brazing material such as 48 bismuth-10 antimony is preferred.

Heat transferred from the chip 10 to the housing 16 via the thermally conductive pad 20 is transferred to a heat sink, such as a cold plate 32, engaged to the housing 16. As seen in FIG. 2, the surface of the housing 16 and the cooling plate 32
The surfaces of the two are flat to allow good heat transfer between the two. A cooling liquid 42 for removing heat transferred to the cooling plate 32 is circulated in the space 32H of the cooling plate 32, thereby achieving efficient cooling. A liquid such as water is desirable as a cooling liquid capable of efficient cooling. Therefore, if the chip 10 to be cooled is maintained in a state where it is not overheated above a pre-designed temperature in the operating state, it is also possible to use an air-cooled heat sink instead of cooling with the cooling plate 32. In this case, consideration must naturally be given to keeping the above-mentioned noise problem to a minimum (24). Similarly, in the heat-conducting module device of the present invention, there is no problem in that the housing 16 made of the silicon carbide sintered body doubles as a heat sink that is in direct contact with the cooling medium outside the enclosed module device.

FIG. 3 is a schematic cross-sectional view showing an enlarged portion of the thermally conductive pad 20 and housing 160 used with the chip 10. The chip 10 has a square shape with a side of 6.5 m, and a metallized layer 10a made of a chromium-nickel-silver laminated metal layer is provided on the side of the chip 10 where the solder balls 11 are not provided, and the metallized layer 10a is made of a chromium-nickel-silver laminated metal layer to improve heat conduction. This contributes to realizing a metallic bond between the sexual pad 20 and the tip 10. Furthermore, a metallized layer 16b made of a chromium-nickel-silver laminated metal layer having approximately the same dimensions is provided on the portion of the housing 16 facing the chip 10, which contributes to realizing metallic bonding between the thermally conductive pads 20 and the housing 16. are doing.

The chromium layer of the metallized layers 10a and 16/b serves to maintain the bonding strength with the silicon or silicon carbide sintered body, and the nickel layer serves to prevent the reaction between the metal (25) constituting the thermally conductive pad 20 and the chromium layer. The silver layer has the role of a stopper for suppressing the thermal conductivity, and the silver layer has the role of providing wettability to the thermally conductive pad 20. Therefore, insofar as each metal layer can fulfill the above-mentioned role,
Can be substituted with other metals.

For example, instead of chromium, titanium, molybdenum, tungsten, nickel, etc. can be used as a layer to maintain adhesive strength.
A metal such as aluminum is used as a stopper, a metal such as copper, palladium, platinum, or aluminum is used instead of nickel as a stopper, and a metal such as gold, platinum, nickel, or copper is used instead of silver as a layer for providing wettability. Metal can be used.

If necessary, a chromium-nickel mixed layer may be provided between the chromium Jf4 and nickel layers to strengthen the adhesion.

These laminated metal layers are formed by vacuum evaporation method,
If necessary, it may be formed using a sputtering method or an ion blasting method. The metallization layers 10a, 16b are effective in enhancing the heat transfer performance of the thermal conductive path. In order to improve the heat transfer performance, it is desirable that the metallized layer of the Uzing is formed after providing (26) fine irregularities on the surface by sandblasting or the like.

Further, the metallized layer 16b may be formed by plating a metal that imparts wettability to, for example, a molybdenum thick film fired metallized layer or a copper-manganese alloy pressure-bonded metallized layer. Similarly, in order to enable wettability and metallic bonding to the sealing member 17 between the protrusion 16a of the housing 16 and the substrate 12, the protrusion 16a is provided with a similar metallized layer (not shown), A metallized layer (not shown) is also provided on the substrate 12 side. The silicon carbide housing is preferably provided with a laminated metal layer consisting of the various metal layers mentioned above, and in the above-mentioned embodiments is provided with a laminated metal layer consisting of chromium-nickel-silver (not shown).
. This sealing part is an important part for keeping the inside airtight, and if the residual strain in the metallized layer forming part becomes excessive, there is a risk that the housing material will break due to temperature changes. The laminated metal layer is a thin film of about 1 to 2 μm and has a great effect in reducing residual strain imparted to the housing. This problem of residual strain also exists in the thermally conductive pad (27) and can be solved in the same manner as described above.

In the embodiments described above, the housing 16 is directly fixed to the substrate 12 by the sealing member 17, but in the present invention, the housing 16 may be indirectly fixed to the substrate 12. FIG. 4 shows an example of this, in which a spacer 15 made of metal or ceramic is arranged around the side of the substrate 12 on which the chip 10 is mounted, and a cap or housing 16 is arranged in series on the other side of the spacer 15. ,
It is fixed by a sealing member 17, 18 such as a brazing material such as solder. With these component configurations, the closed space 19
is formed. The material of the spacer 15 should be selected not from the viewpoint of thermal conductivity but from the point that the coefficient of thermal expansion matches or is similar to that of the substrate 12 and the housing 16. For example, when the substrate 12 is made of alumina ceramic, mullite ceramic, and the housing is made of silicon carbide sintered body, the spacer 15 is made of alumina ceramic, mullite ceramic, silicon carbide sintered body, (28) Kovar, 58Fe-42Ni, tungsten. Materials such as carbide can be selected. The reason for giving priority to the thermal expansion coefficient is the need to avoid fatigue failure of the sealing member that occurs when thermal cycles are applied due to the difference in thermal expansion coefficient between the substrate 12 or the housing 16. be. Furthermore, it is desirable that the metallization layer has as high an adhesive strength as possible with the housing. In the present invention, the adhesive strength can be improved by adjusting the thickness of the chromium layer, for example. - For example, in the case of a chromium-nickel-gold laminated metal layer, the adhesive strength is 2.5 when the chromium layer thickness is 0.1 μm to 7 when the thickness is 0.3 μm.
It can be improved to "Ti1l".

〔Effect of the invention〕

As explained above, the housing 16 of the thermal conduction cooling module device of the present invention is provided with electrical insulation and helium leak resistance as well as high thermal conductivity. It has a consistent coefficient of thermal expansion and is light in weight, and is effective in obtaining a high-performance and highly reliable thermal conduction cooling module.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional perspective view showing an embodiment of the present invention;
2 is a sectional view taken along line AA' in FIG. 1, FIG. 3 is an enlarged view of the main part of FIG. 2, and FIG. 4 is a sectional view showing another embodiment of the present invention. 10...LSI chip, 12...wiring board, 20...
・Thermal conductive pad. Agent Patent Attorney Akio Takahashi (30) No. Z Roa 2 lb Hisaya 30 Kaya 4me zis

Claims (1)

[Claims] 1. A heat generating device to be cooled, a wiring board on which the heat generating device is placed, and a container that is airtightly adhered to the periphery of the wiring board and airtightly surrounds the heat generating device together with the wiring board. a heat conduction member that thermally communicates between the heat generating device and the cap member, and a means for cooling the cap member, the heat conduction member forming a heat conduction member of the cap member and the cooling means. A heat conduction cooling module characterized in that the portion located at is a sintered body mainly composed of silicon carbide, and the heat conduction member is made of a low melting point metal metallically joined to the heat generating device and the cap member. Device. 2. In claim 1, the heat conductive member is selected from the group of bismuth, tin, indium, and mercury.
A single metal or an alloy material containing at least one metal of lead, tin, bismuth, indium, cadmium, mercury, and antimony; ,
a first metal layer made of at least one member selected from the group of nickel and aluminum; at least one member selected from the group of nickel, copper, palladium, platinum, and aluminum;
A second metal layer consisting of a metal layer consisting of a second metal layer consisting of a metal, a third metal layer consisting of at least one metal selected from the group of silver, gold, platinum, and nickel steel - metallurgically bonded through the metal layer A heat conduction cooling module device characterized by: 3.% Permissible claim 1 or 2, wherein the cap member is composed of silicon carbide as a main component and contains at least one member selected from the group of beryllium, beryllium oxide, and boron nitride as an additive. A thermal conduction cooling module device characterized by being a solid body. 4. The thermal conduction cooling module device according to claim 1 or 2, wherein the cap member has an electrical resistivity of 1010 Ω or more. 5. Claim 1 or 2, wherein the cap member contains silicon carbide as a main component, contains at least one selected from the group of beryllium, beryllium oxide, and boron nitride as an attachment, and contains aluminum as an attachment. 1. A heat conduction cooling module device characterized in that it is a sintered body containing at least one of silicon, iron, titanium, and nickel, or an oxide or carbide. 6. A heat conduction cooling module device according to claim 1, 2, 3, 4, or 5, wherein the heat generating device is an LSI chip.