JPS59215797A - Intensified nuclear boiling surface tape and cooling of electronic part - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for cooling electronic components such as integrated circuit devices or chips. More particularly, the present invention relates to the use of enhanced nucleate boiling surfaces and liquid refrigerants to remove heat from electronic components.

The limits on the use of integrated circuit devices are limited by the heat generated by the integrated circuit and the devices for dissipating this heat. As the operating temperature of integrated circuit devices increases, the rate of device damage increases significantly. If the temperature increases by 18 degrees Celsius, the lifetime of integrated circuit devices will be cut in half. Although it is desirable to have integrated circuits placed as closely together as possible in a package with the circuits in close contact, the thermal energy density is high and heat removal becomes difficult. Currently, electronic device designers use less dense arrangements than desired because there are insufficient heat removal techniques.

In particular, to increase the usefulness of computers, integrated circuit devices are packaged, computers are placed closer together, and their operating speeds are increased. This method reduces the amount of heat generated per unit volume of the computer circuit.

In general, individual rod air cooling methods are insufficient for modern equipment. Cooling equipment is large and limits circuit density. An example is the heat sink mounted on a chip carrier as shown in the article ``Package'' published in Electro-Ex Magazine December 29, 1981.

The volume of the heat sink is at least six times that of the chip carrier. There is an upper limit to the amount of heat that can be removed by air cooling. The heat sinks described above can dissipate up to 4.5 W of heat, which is insufficient for many applications.

Heat removal with liquid coolants is more effective than air cooling, and higher heat transfer coefficients can be obtained with liquid systems than with gas systems. Heat is transferred from the solid structure to the walls surrounding the coolant stream by conduction and transferred to the liquid by convection.

A new and effective method of liquid cooling is immersion cooling, which is currently in an advanced stage of development. Electronic components are immersed in a non-conductive coolant and heat is removed by convective transfer. After heat transfer from the electronic device to the refrigerant, a device is provided to remove heat from the refrigerant.

When the heat per unit area, that is, the heat flux, is large, the amount of heat transfer is significantly increased by boiling the refrigerant. Thus, heat is removed by convection when the heat flux is low and by boiling when the heat flux is high. Boiling, or two-phase heat transfer, is significantly more efficient than convective heat transfer from a solid to a liquid.In two-phase heat transfer, thermal energy is transferred by a phase change from liquid to gas. However, there are many problems in designing this device. The first problem is that the temperature of the electronic components rises above a permissible value before boiling begins. A second problem is that current boiling heat transfer devices are too complex to be widely used.

These problems are solved by the use of a so-called strong nucleate boiling surface according to the present invention.

A large amount of research has been conducted to determine how to increase the heat transfer rate from hot surfaces, but most of it is not for cooling electronic components. Certain structural surfaces have been developed that promote nucleate boiling and are referred to as enhanced nucleate boiling surfaces. A common use for this surface is to increase the boiling of the tubes of a tubular heat exchanger, in which liquid in contact with the outer surface of the tube is heated to boiling by the hot fluid flowing within the tube. References on boiling and enhanced nucleate boiling include Hemisphere 7G Bridging Co.'s Panstralen and Cole's Boiling Theory, Physical Chemistry and Technological Fundamentals and Applications, and Heat Transfer Engineering, Vol. 2, No. 3-4;
1981, ``Development of Enhanced Surface Structures for Nucleate Boiling'' and the US patents mentioned below.

Liquid cooling techniques are being developed in conjunction with the coming generations of advanced electronic devices. The way chips are packaged is also changing rapidly. The present invention is useful in the development process described above, and enables efficient cooling of high-density, high-performance electronic devices with minimal equipment. References on packaging techniques include the above-mentioned ``Papackage'' and ``Chip Carrier'' of Electronic Packaging and Production, March 1981.
There is a monthly issue. A review of advanced packaging and cooling techniques can be found in Electronics Magazine, September 22, 1982.

Describe known techniques.

The following U.S. patents describe enhanced nucleate boiling surfaces, U.S. Pat.
No. 7, No. 4136428, No. 4182412, 4199
No. 414, No. 4219078, No. 4288897.

These patents describe methods of providing enhanced nucleate boiling surfaces on heat transfer tubes. A similar nucleate boiling surface is used in the present invention for cooling electronic components. Reference is made to this US patent.

U.S. Pat. No. 4,312,012 discloses a method of treating a silicon integrated circuit surface to obtain improved nucleate boiling properties compared to those of similar untreated surfaces. A document similar to this patent is published in the Journal Onoapprophyte Electrochemistry, 1980, No. LO. Mechanically damaging a surface using the method of this patent is a relatively primitive technique for improving the nucleate boiling properties of a surface, and the degree of improvement is small. Other methods (as shown in the nucleate boiling literature mentioned above) are suitable. Sandblasting according to this patent is a harsh treatment for integrated circuit devices or silicon, and there is no mention of the extent of cleaning and manufacturing precautions when assembling into integrated circuit devices. This patent only deals with forming enhanced nucleate boiling surfaces on the integrated circuit device itself. The present invention can create an effective nucleate boiling surface in any desired plane and select the preferred endpoint of the heat path from the integrated circuit device. Therefore, the integrated circuit device used in the present invention does not need to be immersed in liquid. U.S. Pat. No. 4,053,942 states that it is reassuring that the refrigerant is extremely pure for immersing integrated circuit devices, and describes an apparatus for maintaining purity. Avoiding direct immersion of the device to be cooled will preserve the purity of the refrigerant8.
This is suitable because there is no climbing.

U.S. Patent No. 4 to improve nucleate boiling characteristics by drilling holes in the surface.
It is written in No. 050507. This hole is drilled with a high-energy beam. In one embodiment, bubbles are generated by a heater near the treatment surface to promote nucleate boiling on the surface. U.S. Patent Nos. 3,993,123, 4,156,458, 432,273
No. 7 shows the structure of a pack for cooling integrated circuits.

US 1J-Patent No. 3,512,582 shows an immersion cooling device,
A central reservoir is used for multiple modular units containing heat generating components. There is no description of the enhanced nucleate boiling surface in this document. US Pat. No. 4,203,129 shows cooling of highly parallel integrated circuits. As will be explained below, the present invention does not require the complex apparatus described in this patent.

It is an object of the present invention to provide an improved apparatus and method for cooling electronic components in which heat is removed by a refrigerant liquid.

Another object of the present invention is to increase the amount of heat generated per unit volume of an electronic circuit so that the operating temperature of the circuit does not become too high.

Another object of the present invention is to provide a heat removal method and apparatus which is simpler than known apparatus.

Another object of the invention is to enable control of the heat path from the location of heat generation to the location of transfer to the waste refrigerant.

Another object of the present invention is to provide techniques for assembling electronic devices using commercially available components and techniques for manufacturing second components.

Another object of the present invention is to provide an enhanced nucleate boiling surface tape that can be dimensioned to be attached to electronic components.

The enhanced nucleate boiling surface tape according to the present invention comprises a thin metal layer and an open cell reticulated organic foam deposited on one side of the thin metal layer.
and a metal deposited on the foam material by plating.

The enhanced nucleate boiling surface tape according to the invention comprises a thin metal layer and a coating consisting of a metal deposited by electroplating and a number of powdered conductive particles completely or partially surrounded by the deposited metal.

An example of the process for manufacturing this nucleate boiling surface tape is to place a thin metal layer shielded on the negative side in a plating solution containing conductive particles, bring the thin metal close to the metal source to be plated, Connect a power supply to the metal source to plate the metal from the metal source, stir the plating solution to keep the conductive particles in the solution and adhere to the thin metal, and at least some of the conductive particles adhered to the thin metal. Metal plating is applied surrounding the area.

In accordance with the present invention, the above-described enhanced nucleate boiling surface tape can be attached to an integrated circuit device package as required dimensions.

The thin metal piece is shielded during manufacturing to keep this surface suitable for package attachment.

A package for an integrated circuit device according to the present invention includes the above-mentioned enhanced nucleate boiling surface tape on at least a portion of the surface of the package of the integrated circuit device at a predetermined location for forming a thermal path between the heat generating area of the package and the boiling surface. Attach to. Thin metal can be attached to the package at eye II where the foam is attached and plated metal is applied, or a fully formed boiling surface can be attached to the package.

An example of electroplating is to perform pneumatic plating of a thin metal layer protruding under the pores of a reticulated foam material to form a generated metal surface that overlaps and adheres to the surface of the thin metal layer. is formed by following the pores of the foam material and extending outward from the surface of the foam.

Another example of electroplating is that the plated metal is 81!1
As a step, electroless plating is performed on the foam material, and as a second step, electroplating is performed to form a reticulated metal surface with a thin metal layer adhered to the W metal layer.

In another embodiment, an adhesive coating of Graphide is applied to the foam material prior to application of the plated metal, and the plated metal adheres to the thin metal layer with the Graphide, forming a reticulated opening overlying and bonding over the thin metal layer. Cells form metal surfaces.

In accordance with another embodiment, at least a portion of the reticulated metal structure formed by the plated metal is heated to heat the boiling surface tape to pyrolyze at least a portion of the foam material into a hollow metal skeleton comprising a hollow metal system, thereby forming a core. When the boiling surface tape is placed in a liquid boiling medium, it traps vapor and releases a portion of the vapor through a number of small holes in the framework that form the gas phase nucleation zone.

In another embodiment, a hollow metal system at a boiling surface is pressed against a plurality of solid particles to deform a portion of the hollow metal system to reduce its internal diameter and reduce its ability to transport liquid along the length of the hollow opening. do.

Other embodiments include thin metals and/or plated metals such as copper and I-stone.

According to another embodiment, the enhanced nucleate boiling surface is attached to the integrated circuit device package by an adhesive or a fusible metal alloy. Machine the boiling surface to reduce thickness and improve boiling properties. The package consists of a chip carrier, a pin grid array, and a pad 8 grid array.

A cooling device for removing heat generated by an integrated circuit device according to the present invention includes an integrated circuit device, an enhanced nucleate boiling surface tape having the above-described configuration, and a heat path for conveying the heat generated by the integrated circuit device to the boiling surface. a liquid refrigerant that is heated in contact with the boiling surface; and means for removing heat from the refrigerant.

Embodiments and drawings illustrating the present invention will be described.

In order to cause liquid boiling on the hot surface that is to be cooled by the contacting liquid, bubbles must be generated. Some minimal superheating is required for bubble generation. Superheating is the temperature difference between a hot surface and the boiling point of a liquid, making the boiling point a lower temperature.

If the superheat value is below the minimum value, heat is transferred by convection and no phase change occurs in the plane. The necessary superheat value for boiling to begin is determined by the nucleation characteristics of the hot surface. Steam bubbles form at depressions in the hot surface, ie, at nucleation sites. If the high-temperature surface is smooth, there are fewer nucleation positions, and a large superheat value is required to cause strong boiling on the high-temperature surface. For non-smooth surfaces, small superheat values are usually sufficient to produce strong boiling. For some types of surface roughness, small superheat values are sufficient for bubble formation and two-phase heat transfer takes place.

A smooth hot surface is otherwise identical to the rough surface described above, supplies the same amount of heat, and when immersed in the same bath requires a larger temperature difference than the rough surface for boiling. The large superheat values required to produce strong nucleate boiling in smooth-surfaced electronic components often result in excessive processing temperatures for the electronic components.

Two types of boiling are observed. They are nucleate boiling and film boiling. Film boiling is a later stage. When boiling starts, it is always nucleate boiling, and bubbles are first formed on the high temperature surface. The more the heat flux on the high temperature surface increases, the more σ? Air bubbles are formed. Film boiling occurs when the generation of bubbles increases significantly and the bubbles coalesce to form a continuous film on the hot surface. The membrane acts as an insulator for hot surfaces. Thus, once film boiling begins, the cooling efficiency decreases, and the surface temperature becomes higher than that of the portion where the core θ rises.

For this reason, it is desirable to avoid film boiling.

The principle of thermal resistance is used in the treatment of heat transfer devices.

Heat flows out of the heat generating device by hitting the heat path. If the outer envelope of a heat generating device is not uniform, heat will flow out of the device unevenly and will follow the thermal path that provides the least thermal resistance to heat flow. Thermal resistance can be calculated for each section and the resistances can be added to obtain the total thermal resistance.

In the case of the present invention, the thermal path consists of a number of thermal resistances, where conduction is the heat transfer mechanism and the final resistance is where convection or boiling occurs. The maximum thermal resistance among a series of thermal resistances forming one thermal path is called a control resistance. For a given thermal resistance to be a controlled resistance, it needs to be significantly larger than the sum of the other thermal resistances in the thermal path. If a resistance is a controlled resistance, changes in other various thermal resistances have little effect on determining the amount of heat conducted from the heat generating device. Materials and dimensions can be selected to reduce the thermal conduction resistance in the thermal path, making the final convection or boiling resistance a controlled resistance.

In the equation of FIG. 1, K is the thermal conductivity of the material. This is the amount of heat that passes in one hour when the thickness is 1 inch, the cross-sectional area is 1 square inch, and the temperature difference across the thickness between the two sides is 1'F. K
The unit of can also be expressed in the metric system, and it can be easily shown as shown in Figure 1 by combining the terms of area and length. R is the thermal resistance, which is obtained by the calculation shown in FIG. 1 using the length and cross-sectional area of the thermal path. The two equations at the top of FIG. 1 show that the units and numbers of items to be added are equal, and can be used to convert into actual numerical values.

A simple numerical example using the assembly shown in FIG. 2 will demonstrate the effectiveness of the invention and clarify the principles. In FIG. 2, the chip 1 is attached to an alumina substrate 31 with an adhesive 30. The enhanced nucleate boiling surface 11 of the present invention is adhered to an alumina substrate 31 with an adhesive 30. The calculation example shown in FIG. 1 shows the calculation of the temperature of the tip l with and without the enhanced nucleate boiling surface 11.

A case where the coolant contacts the surface alumina substrate 31 and a case where the coolant contacts the enhanced nucleate boiling surface 11 are shown. The amount of heat that escapes from the surface of the chip and the substrate to the outside air is assumed to be negligible, and the heat generated in the chip is ioquats per 1LrL2 of the chip. Adhesive thickness is 0.003trL (approximately 0.08mm)
It is assumed that the solder is 0.2 and the thermal conductivity is 0.2. Base thickness l
/Btl (approximately 3 mm) K207. According to the experimental results in the refrigeration and air conditioning department, the addition of the enhanced nucleate boiling surface of the present invention results in an improvement of y - orders of magnitude. , the aluminum base 31 has R=3.0.

In Figure 1, if the thermal resistance is increased and the product with the generated heat is calculated, the superheat value will be 32°C if there is no enhanced nucleate boiling surface, and 5°C if there is. This is a significant temperature difference.

If the coolant is 30°C, it will be 62 when there is no enhanced nucleate boiling surface.
℃, and in the case of the present invention, it is 35℃. The heat path shown in FIG. 2 is similar to that in FIG.

If copper of the same thickness is used instead of the alumina base 31,
Copper = 9.94, and when the boiling surface 11 is not used, the superheat value will be 30°C instead of 32°C, and if enhanced nucleate boiling surface repair is used, it will be 3°C instead of 5°C.

From this example we see that the thermal resistance of the boiling surface is a controlled resistance and therefore an enhanced nucleate boiling surface is required.

Replacing the thermal path with a good conductor does not significantly affect the chip temperature, which is significantly improved by the present invention. The aforementioned documents demonstrate the importance of the principle of controlled resistance.

Referring to Figures 1 and 2, in the above example the thermally conductive epoxy cement, 0.005 LrL (approximately 0.1 mm) thick, K
If -062 is replaced with the solder adhesive 30, the calculated chip temperature becomes 34°C and 10°C. Even though epoxy is a thermally conductive epoxy, its thermal conductivity is poor. Even so, the effect is small compared to the enhanced nucleate boiling surface. A document dealing with the above-mentioned numerical example method is described in ``Tube Handling Technique for Keeping Semiconductors at Low Temperature'', Electronics, September 25, 1980.

Experiments demonstrate significant improvements according to the present invention.

In FIGS. 4A and 4B, a modified/reconverted chip 1 is placed into an integrated circuit device package 2. Package 2 is a chip carrier manufactured by Kiyocera Kai International Co., Ltd. (Kyocera/16sD-560-
8131) with a 048 mm square (approximately 12.5 mm). Thermal conductive and electrically insulating epoxy cement 3
Attach chip 1 to package 2 using the . Two thin copper sheets 4 forming an electrical conductor 4 provide a current path between the chip 1 and the gold conductor 6. Also, the conductor 6 is a part of the .xi.cage 2. The chip carrier used in this experiment had ten gold conductors 6 on each side, eight shown in the figure. There are 40 conductors in total, which are commonly used to connect circuits to the chip. As shown in Figures 4A and 4B, ξ
Gold conductors 6 on only two sides of the cage 2 are used in the illustrated example. The other end of the current carrying gold conductor is a conductive epoxy cement 5
Attached to the copper strip 7 by the vc. A conductive wire 8 is attached to a device (not shown) to supply various measured values of current to the chip l.

Thus, the heat generated by an integrated circuit device can be estimated by passing an appropriate current through the chip l for steady-state operation. The cover 12 is part of the integrated circuit device ξ cage 2 and is held in place by adhesive 9. A thermocouple is attached to the center of the chip 1 using thermally conductive epoxy cement 3, and a lead wire 10 is connected to a device (not shown) through the cover adhesive 9 to measure the chip temperature.

The package supported by the conductor 18 is immersed in the fluorocarbon refrigerant 11. Refrigerant 11 has a boiling point of 70°F (
approximately 22°C). A current is passed along the tip l. Record the chip temperature for each input terminal. This result is shown by the curve Avc in FIG. 5, and the chip temperature shown as the overheating temperature is shown relative to the chip supply power. A discontinuity in the curve likely indicates the onset of film boiling.

After obtaining the data of curve A in FIG. 2, an enhanced nucleate boiling surface 11 was bonded to the package 2 with a thermally conductive epoxy cement 3. Enhanced nucleate boiling surface 11 was prepared by the method shown in US Pat. No. 4,136,428. As shown in FIG. 3, a thin copper film laminate 21, epoxy, and fiberglass were sequentially adhered to an insulating backing plate ZO, with the fiberglass being used to support the laminate 21. Laminations were used because readily available, flat copper films are difficult to obtain and can shield one side of a thin metal. Grahyde impregnated foam 22 was placed on the exposed copper side of laminate 21 and held in place by large cell foam 23. Copper cathode 24 with large cell foam material 2
I glued it to 3. The purpose of the large cell foam 23 is to support the graphide-impregnated foam 22 and to form part of the gap between the electrodes. To produce graphide-impregnated foam 22, an open-cell reticulated core is impregnated with graphite powder, and the foam is passed through a shear mill. The shear mill has two rollers that rotate at different speeds, and the foam material passes through a small opening between the two rollers. A Santoichi structure (not shown in Figure 3) is placed in sulfuric acid steel and a direct current is passed through it. Once enough planes 1 have been plated on the copper foil and graphide surfaces, the laminate 21 is heated with a laboratory gas flame to remove the epoxy and fiberglass. The heating causes at least a portion of the foam material 22 to
Pyrolyze as shown in No. 428. A member made of thin copper foil, graphide, and plated copper with this configuration is called a reinforcement core tape.

The package 2 with the reinforcement nucleus V eye blood 11 attached is cooled with refrigerant ll.
Data were obtained in the same manner as for curve A in FIG. 5 above. Curve B in FIG. 5 is the result of measurement using a thermocouple attached to the nap l with epoxy cement 3 to measure the temperature of the chip l, and the measurements were made at various human power values as before. By comparing curves A and B, the effectiveness of the present invention can be understood. As shown by curve BK, the overheating of the chip does not exceed 25°F (approximately 14°C) even at a significantly high human power of 35 watts. Core part of the present invention) When no blood is attached, the temperature of tip 1 is 3 when the human power is 25 watts.
The temperature rose to over 10'F (172°C). Using the present invention, it is possible to increase circuit density beyond what is currently available.

This experiment and curve 5 in Figure 3 of U.S. Pat. No. 4,312,012.
A comparison with the data shown in No. 4 shows that the present invention is a significant improvement. However, since the present invention is not a comparative experiment, there are numerical differences. Not shown in U.S. Pat. No. 4,312,012, silicon wafers have a heat flow of about 2 W/cr of the wafer.
At ri2 the superheat value was about 14°C. package 2
Therefore, if 1n is used for 1 history and 2W/'cTrL2 is converted into a value compared to that shown in FIG. 5, the adjusted heat flow of US Pat.
The superheat value of 14°C is y25°F. As shown in Fig. 5, even if the human power value becomes 35WK, which is extremely large, the superheat value does not exceed 25°F.

Therefore, compared to U.S. Pat. No. 4,312,012, 35W vs. 3
It becomes W. Although a direct numerical comparison does not provide exact quantitative results, this difference G indicates that the present invention is a significantly more effective cooling method. In this case, the area of package 2 was used instead of the area of chip 1. The improvement in cooling is significantly greater when compared with the area of the chip 1.

The disclosures of the aforementioned US patents are incorporated herein.

These patents detail methods for producing enhanced nucleate boiling surfaces. In particular US Pat. U.S. Pat. No. 4,138,428 shows a reticulated foam fiber coated with a sized mesh. US Patent 418241
No. 2, No. 4,199,414 describes a method for making an enhanced nucleate boiling surface that does not use reticulated foam material as the boiling surface element. US patent 4
No. 136,427 shows electroplating on a thin metal surrounding the foam and shows machining to better characterize boiling surface performance. US Pat. Nos. 4,219,078 and 4,288,897 show that enhanced nucleate boiling surface elements can be modified to improve performance.

These patents show the mounting of an enhanced nucleate boiling surface on a tube, and when these patents are combined with the manufacturing method shown in FIG. Show that it can be manufactured.

The present invention allows the design engineer to control the location of maximum boiling and define a low thermal resistance path to direct heat to the optimal location for heat transfer. The enhanced nucleate boiling surface can be mounted at an optimal location on the integrated circuit device package. child~
The package used for this purpose includes not only structures surrounding all or part of the chip, but also structures connected to the integrated circuit device and the integrated circuit device itself, as long as there is a portion for attaching the enhanced nucleate boiling surface. The enhanced nucleate boiling surface prevents hot spots and evens out the temperature of the package and structure. Although the present invention does not require the fabrication of the enhanced nucleate boiling surface to be carried out simultaneously with the fabrication of the integrated circuit device and package, it is a significant advantage of the present invention that the boiling surface can be installed during assembly of the gutter device from off-the-shelf parts. For example, a chip carrier with a metallized side can be used to practice the invention, by attaching a reticulated foaming agent to the metallized side of the carrier.
'An enhanced nucleate boiling surface can be obtained by electroplating. To attach the Core II side tape to the metal-coated surface of the package, adhere with thermally conductive epoxy.

Nucleate boiling surfaces can be manufactured to exact dimensions and shapes.

The present invention is applicable to various packages and components. For example, a chip l in a package 2 shown in FIGS. 5A and 5B is mounted on a substrate 31 with a large number of IJ-domains m14. In the package shown in FIG. 6A, the cavity is in the upper position, the enhanced boiling surface 11 is attached to the substrate 31vC, and the thermal path includes the substrate. This configuration does not require coolant to contact the package.

The substrate forms part of the coolant reservoir, allowing the chip to be inspected without draining the coolant. The multiple boards each consist of multiple chips on a substrate and are incorporated into the cage similar to the plates of a heat exchanger. Install each set of adjacent boards, with the nucleate boiling surfaces facing each other. As a result, the shape is such that spaces for accommodating the refrigerant and spaces for attaching the packages are arranged alternately. In FIG. 6B, the cavity is in the lower position of the package, and the enhanced nucleate boiling surface 11 is attached to the package.
The thermal path does not pass through the substrate 31.

Figures 7A and 7B illustrate another way of carrying out the invention, 1
A hypothetical packaging device is shown in the September 27, 979 issue of ``New Connection Techniques'' published by Electro-X magazine. A polymer film 40 covers the chip l, which is attached to the substrate 31. The position of the enhanced nucleate boiling surface 11 is determined as desired by the design engineer.

For example, a conduction piston as shown in US Pat. No. 4,203,129 can be used as part of a thermal path to conduct heat from an integrated circuit device to an enhanced nucleate boiling surface. Because the present invention has a large degree of freedom in design, it does not require a device to keep the refrigerant completely free from contamination, as shown in US Pat. No. 4,053,942.

Water can also be used to cool liquid dielectric refrigerants, eliminating the need for careful disassembly for repairs to prevent contamination. Mechanical refrigeration systems are typically used to liquefy the refrigerant extracted as a gas, and its operation is similar to standard refrigeration systems.

The above-mentioned thin metal layer and thin metal foil are based on normal usage.

That is, in most applications of the invention, the metal is thin enough to accommodate subsequent manufacturing steps or provide the required mechanical strength.

This thickness is irrelevant to the features of the invention.

For example, if a multi-thickness metal member is used in the packaging of an integrated circuit device, an open cell reticulated organic foam can be attached to the member and plated with metal to form a boiling surface. Typically, the foil from which enhanced nucleate boiling surface tape is made is such that the tape can be easily bent and attached to curved or irregular surfaces.

Copper is a metal commonly used in heat transfer devices because of its thermal properties. However, the metal thin layer or metal foil of the present invention may be any metal as long as it is compatible with the manufacturing method of the present invention. Similarly, the metal to be plated or vapor deposited is not limited to copper, but may be any metal that can be vapor deposited.

[Brief explanation of the drawing]

Figure i1 is a diagram showing calculation of a numerical example comparing the temperature of a chip cooled using the enhanced nucleate boiling surface of the present invention and a normal chip cooled in the same way, and Figure 2 is a partial cross-sectional view of the chip attached to a substrate. , Fig. 3 is a partial sectional view showing the manufacturing process of the enhanced nucleate boiling surface of the present invention, Fig. 4A and Fig. 4B show the chip carrier and chip assembly used in the experiment, and Fig. 4A shows a part removed. The plan view and Figure 4B are cross-sectional views taken along the line 4B-4B in Figure 4A, and Figure 5 shows the chip carriers shown in Figures 4A and 4B, which are packaged in a liquid tank with and without an enhanced nucleate boiling surface. Figure 6A is a graph showing this, and Figure 6 is a cross-sectional view showing the enhanced nucleate boiling surface applied to the package, Figure W7A. FIG. 7B is a cross-sectional view of attaching an enhanced nucleate boiling surface to a chip covered with an M polymer film. ■60. Chip 2...Package 3.5
．． 9.30...Thermal conductive evokin cement 4.7,
8.14...Conducting wire 6...Gold conductor 10...Thermocouple 11...Enhanced nucleate boiling surface 12.40...
Cover 20... Back plate 21... Copper foil lamination
22...Graphide-impregnated foam material 23...Large cell foam material 24...Copper cathode 31...Substrate Patent applicant N.O.P. Inc. Patent attorney Patent attorney Kyo Yuasa (3-1) (4 others) Engraving of the drawings (no changes to the contents) FIC62l bow rG, 3 I7a ri A 7'I&', '$/3 17G 6β F'l', 713 Mr. Kazuo Wakasugi, Commissioner of the Patent Office 1, Indication of the incident Showa year patent application No. r=tt?t No. 2, name of invention J Yuki, Oship An throat δb Chi76β1/1 ↓
Poore9-n Nakaimo, ``Relationship with the case of the person making the amendment Patent applicant's address
, □4 Written amendment to agent procedure (method) 1. Indication of the case (Showa 2011 Patent Application No. -r'h') No. 7,
Relationship with the case of the person making the amendment Applicant Address 8 5F! I Yuohhi°-・I7Ko Kanashi Ichi・
Do 4, Agent 5, Date of amendment order Showa Era Childhood G month μ day (shipment date)'; , Figure 6B". Above all

Claims (1)

[Claims] 1. A thin metal layer, an open cell reticulated organic foam material deposited on one side of the thin metal layer, and a metal deposited on the foaming agent by plating. Enhanced nucleate boiling surface tape. 2. A patent in which the plated metal is electroless plated on the foam material as a first step and electroplated as a second step to form a net-like metal surface that covers the thin metal layer and is fixed to the metal layer. The tape according to claim 1. 3. Ivi. The plated metal is electroplated on the surface of the thin metal layer exposed below the pores of the reticulated foam material to form a biomechanical metal surface that overlaps and adheres to the surface of the thin metal layer; 4. The tape of claim 3, wherein the generated metal surface extends outwardly from the exposed surface through the pores of the foam material. 4. Before applying the plated metal, apply granite adhesive to the foam material 11C, and the plated metal firmly adheres to the thin metal layer and clarhide to form a net-like structure in which the plated metal overlaps and adheres to the thin metal layer. A tape according to claim 1 forming an open cell metal surface. 5. Heat the tape to thermally decompose at least a portion of the foam material to form at least a portion of the mesh metal structure formed by the plated metal into a hollow metal skeleton made of a hollow metal system, thereby forming a nucleate boiling surface tape. 2. A tape as claimed in claim 1 which, when placed in a liquid boiling medium, retains vapor and releases a portion of the vapor through a number of small holes in the framework forming a vapor phase nucleation zone. 6. A patent in which the hollow metal system of the boiling surface is pressed against a plurality of solid particles to deform a portion of the hollow metal system to reduce the inner diameter and the ability to transport liquid along the length of the hollow opening. The tape according to claim 5. 7. Enhanced nucleate boiling, characterized in that it comprises a thin metal layer and a coating consisting of a metal deposited by electricity and a large number of powdery conductive particles completely or partially surrounded by the deposited metal. Velcro tape. 8 In the process of manufacturing the above-mentioned tape, a thin metal layer shielded on the negative side is placed in a plating solution containing conductive particles and brought close to the metal source to be plated on the thin metal. Plating the metal from the metal source by connecting a power source, stirring the plating solution to keep the conductive particles in the solution and attaching them to the thin metal, surrounding at least a portion of the conductive particles attached to the thin metal, and plating the metal. 9. The tape according to claim 7, wherein the boiling surface is machined to reduce the height. 10. The tape according to claim 1 or claim 7, wherein the boiling surface is machined to reduce the height. 10. The thin metal. The tape according to claim 1 or 7, in which the layer is copper. ii. The tape according to claim 1 or 7, in which the deposited metal is copper. The enhanced nucleate boiling surface tape according to item 1 or 7 is applied to at least a portion of the surface of the integrated circuit device package) at a required location for forming a thermal path between the heat generation site of the cage and the boiling direction. An integrated circuit device package characterized by being attached to. 13. A cooling device for removing heat generated by an integrated circuit device, which comprises an integrated circuit device and claim 1 or 7. an enhanced nucleate boiling surface tape described in TJ; means for forming a thermal path for conveying heat generated by the integrated circuit device to the boiling surface; a liquid refrigerant heated by contacting the boiling surface; and means for removing a refrigerant from the refrigerant.