JPS61115666A - Manufacture of heat exchanging body - Google Patents

Abstract

PURPOSE:To manufacture a cooler for integrated elements excellent in cooling ability by joining a metallic plate on which grooves are formed by photoetching and another metallic plate under specific conditions using a specific low melting point metallic plate. CONSTITUTION:A plate 5 on which cooling grooves are formed by photoetching and a plate 6 for upper cover are put in a vacuum container. An oxide film adhering on the surface of the metallic plates is removed by irradiating an argon ion beam. Then, a thin film of low melting point metal such as copper- titanium alloy, etc. is formed on the surface of the metallic members by sputter vapor deposition in the same container. The grooved plate 5 on which the thin film is formed and the plate 6 for upper cover are superposed and put in a vacuum furnace, and a cooler 1 is manufactured by heating and joining at joining pressure of about 0.1-0.3kg/mm<2>. Thus, a cooler having high cooling efficiency and free from blockage of coolant passage is manufactured.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to a method of manufacturing a heat exchanger, particularly an IC.

The present invention relates to a method for manufacturing a heat exchanger suitable for use as a cooler for semiconductor devices such as LSIs and thyristors.

[Background of the invention]

It can be increased by increasing the degree of integration of constituent elements such as ICs and LSIs.
First, the amount of heat generated increases, and cooling is required to improve and maintain performance. The development of coolers with good cooling performance is also the key to increasing the degree of device integration. Furthermore, as the capacity of semiconductor devices such as thyristors increases, the development of efficient coolers has become an important issue. Conventional semiconductor devices have been manufactured by mounting them on a heat dissipating plate having heat dissipating fins, and a representative example thereof is shown in Japanese Patent Application Laid-Open No. 56-88344. The refrigerant entering from the refrigerant inlet 8 flows under the element 4 and exits to the outlet 14 to cool the element. Reference numeral 2 is a refrigerant passage, 3 is an electrical insulating plate, and 1 is a cooler. However, as mentioned above, as the degree of integration of elements increases year by year, it is necessary to take measures to further improve cooling performance. For this reason, although research and development have been carried out to date regarding the structure of the cooler and how to manufacture it, the current situation is that no technology has been developed that fully satisfies these requirements. Conventionally, as a method for manufacturing a cooler of this type, as shown in FIG. 7, a brazing material 7t is placed between a cooling groove machined plate 5 in which cooling grooves 9 are formed by cutting and an upper lid plate 6, and a brazing method is used. It is made by joining. However, since mechanical cutting and brazing methods are used, the depth and width of the cooling grooves cannot be made small. If the depth and width of the cooling grooves are reduced, a problem arises in that the cooling passages are blocked by the brazing filler metal flowing into the cooling grooves and the coolant does not flow. Reducing the width of the refrigerant passages and increasing their number is an important matter in increasing the heat transfer area and increasing the cooling efficiency, but this is completely impossible using the brazing method. In addition, solid phase welding can be considered as a joining method to reduce the width and depth of the cooling groove, but IK at high temperatures
Since a large bonding pressure of 9/2 or more is required, there is a problem that the cooling passage may be deformed or even clogged, and it cannot necessarily be said to be a reliable bonding method.

[Purpose of the invention]

An object of the present invention is to provide a method for manufacturing a heat exchanger that allows fine refrigerant passages to be joined without crushing them even if they are arranged at high density.

[Summary of the invention]

The present invention was developed based on the idea that there are limits to conventional methods of forming refrigerant passages by mechanical cutting, brazing, and in-phase bonding, and that a new type of cooler should be developed to replace this. This was developed as a result of research. In the following description, a plate means a plate having a thickness of several tens of μm or more.

In the present invention, as shown in FIGS. 1 and 2, predetermined fine cooling grooves 9 are formed by photoetching on at least one of at least two plates, and these plates are joined to form a coolant passage. It is something. After cleaning the bonding surface with an Ar ion beam or the like in a non-oxidizing atmosphere during bonding,
It has been discovered that fine refrigerant passages with excellent airtightness can be obtained by forming and bonding metal trowels or alloy films by vapor deposition or sputter vapor deposition.

In the present invention, by employing photoetching to form cooling grooves that serve as coolant passages during bonding, cooling grooves of several tens of micrometers or more can be freely formed, making it possible to create fine cooling grooves that are impossible with conventional mechanical cutting. It is possible to form Furthermore, after cleaning the joint surface with an Ar ion beam or the like in a non-oxidizing atmosphere, a metal or alloy film for joining is formed on the joint surface to be thinner than the total depth of the cooling groove, and the refrigerant passage is blocked. It can be formed without any problem. The technical reason for this is as follows. The surface of the metal plate used as the raw material is usually covered with a contaminated film or an oxide film, so solid-phase bonding of the metal plate as it is requires extremely high temperature and high bonding pressure, which tends to cause deformation. In particular, does a plate made of aluminum or its alloy have a dense and stable oxide film? Therefore, joining is extremely difficult. As a result of various studies on this problem, the present inventors first removed and cleaned the contaminated film and oxide film on the bonding surface using an Ar ion beam in a non-oxidizing atmosphere, and then applied carbon to the bonding surface.
For u, an alloy film such as Cu-Ti series having a melting point lower than that of the material, and for At, an alloy film such as At-8i series is formed thinner than the depth of the cooling groove by vapor deposition or sputter deposition, and the bonding method is kill. It has been discovered that this method enables bonding at low bonding pressure, without fear of deformation, and without clogging of the refrigerant passage due to melting of the metal or alloy film.

One way to improve cooling performance is to increase the heat transfer area as much as possible. Figure 3 shows cooling grooves formed on both sides of one plate by photo-etching and then attached to the other two plates.
This is a cross section of a cooler sandwiched between two plates. Fourth
The figure shows a cross section of a cooler obtained by forming cooling grooves on one of two plates by photo-etching, and then joining the plates with the cooling grooves staggered so that they are arranged in a staggered manner. In this way, fine refrigerant passages can be arranged with high density, resulting in a cooler with even higher performance.

In addition to metals, it is also possible to use ceramics as a material on one side. Since photoetching of metal is easy, a cooler with high cooling performance can be obtained by forming cooling grooves on the joining surface of metal and joining ceramics with electrical insulation and high thermal conductivity. Note that when the cooler is made entirely of metal, it is desirable to mount elements such as LSI on a ceramic substrate and then bond and fix them to the cooler.

The above describes a method in which cooling grooves are formed by photo-etching, then a metal or alloy film is formed, and then bonding is performed. There is no problem.

That is, since the cleaning process is performed using an Ar ion beam or the like, a metal or alloy film with very good adhesion can be formed, so even if photoetching is performed, problems such as peeling of the film do not occur.

[Embodiments of the invention]

Embodiments of the present invention will be described using FIGS. 1, 5, and 6.

@0.1 m formed by photo etching with the upper cover plate 6 made of a copper plate with a plate thickness of 0.5 wrxr shown in FIG.
A cooling groove machined plate 5 made of a copper plate having cooling grooves with a depth of 0.06 m is prepared, and these are placed in a vacuum chamber and each joint surface is irradiated with an ion beam A and cleaned. Cu-30'1 was deposited by sputter deposition in the same vacuum container.
A tTi alloy film of 24 m was deposited and stacked as shown in FIG. Next, the pieces were placed in a vacuum furnace and bonded at 940C, 0.2 for 1 hour at a bonding pressure of 9f/2 to integrate them, and fabricated on a cooler as shown in FIG. Finally, refrigerant inlet 8, outlet 1
1 was completed by brazing the pipe as indicated by the dotted line and using cooler 1. A good refrigerant passage was created without any blockages in the refrigerant passage.

Note that the refrigerant inlet, #, and outlet pipes can be connected all at once when joining the plates without having to perform the brazing process described above, if the pipes are placed at the refrigerant inlet and outlet and joined after the metal or alloy film is formed. can. Reference numeral 10 is a refrigerant reservoir groove.

Although the above explanation has been made regarding the cooler, it goes without saying that the same applies to the heater.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, fine refrigerant passages, if necessary, refrigerant passages of 0.1 days or less can be freely formed, so that a cooler with high cooling efficiency can be realized. Furthermore, by performing all the steps of cleaning the bonding surfaces of the plates and forming the bonding alloy film in a non-oxidizing atmosphere, it is possible to easily manufacture a heat exchanger with high bonding strength and airtightness.

[Brief explanation of drawings]

1 and 2 are plan and side sectional views showing a cooling component of the present invention, FIGS. 3 and 4 are perspective views of a cooler of the present invention, and FIG. 5 is a stacked state of the present invention. Schematic perspective view of 6th
The figure is a perspective view showing a completed product of the cooler according to the present invention, and FIG. 8 is a conventional cooler. FIG. 9 is a perspective view showing the installation process of the conventional cooler, and FIG. 9 is a plan view and a sectional view of a conventional cooler. DESCRIPTION OF SYMBOLS 1...Cooler, 2...Refrigerant passage, 3...Electrical insulating board, 4...Element, 5...Cooling groove processing plate, 6...Upper cover plate, 7...Waffle Material, 8... Refrigerant inlet, 9...
- Cooling groove, 10...Groove for refrigerant reservoir, 11...Refrigerant outlet.

Claims (1)

[Scope of Claims] 1. A heat exchange body in which a metal member having grooves serving as a passage for a heat exchange medium and another metal member are brought into contact and joined, and by the joining, a flow hole for the medium is formed. The manufacturing method includes a step of forming the groove by photoetching, and a step of interposing a metal layer having a lower melting point than any of the metal members on the contact surface, and the method includes a step of forming the groove by photoetching, and a step of interposing a metal layer having a lower melting point than any of the metal members on the contact surface, A method for manufacturing a heat exchanger, which is characterized by heating and bonding at a temperature that does not exceed 100 degrees. 2. A method of manufacturing a heat exchanger according to claim 1, characterized in that the thickness of the metal layer is smaller than the depth of the groove. 3. In claim 1, the contact surface has a diameter of 0.
A method for producing a heat exchanger, characterized by joining under pressure of 1 to 0.3 kg/mm^2. 4. A method for manufacturing a heat exchanger according to claim 1, characterized in that the metal layer is formed by sputter deposition. 5. A method of manufacturing a heat exchanger according to claim 1, wherein the metal layer is made of foil. 6. A method of manufacturing a heat exchanger according to claim 1, characterized in that the metal layer is directly formed on at least one of the contact surfaces. 7. A method of manufacturing a heat exchanger according to claim 1, wherein the metal member is made of copper. 8. Claim 7, wherein the metal layer is made of copper.
A method for producing a heat exchanger characterized by being made of a titanium alloy. 9. A method for manufacturing a heat exchanger in which a metal member having grooves that serve as passages for a heat exchange medium and another metal member are brought into contact and bonded, and the bonding forms flow holes for the medium. a step of directly forming a metal layer having a lower melting point than any of the metal members on at least one of the contact surfaces, and removing an oxide film on the surface of the metal member when forming the metal layer. A method for manufacturing a heat exchange body, comprising the step of heating and joining at a temperature higher than the melting temperature of the metal layer and at a temperature at which the metal member does not melt. 10. Manufacturing a heat exchanger according to claim 9, characterized in that the oxide film removal treatment is performed by placing the metal member in a vacuum and irradiating the contact surface with an argon ion beam. Law. 11. A method for manufacturing a heat exchanger according to claim 9, characterized in that the metal layer is formed by sputter deposition. 12. A method of manufacturing a heat exchanger according to claim 9, characterized in that the thickness of the metal layer is smaller than the depth of the groove.