KR101137917B1 - Process for producing aluminum nitride joint product - Google Patents

Abstract

The manufacturing method of the aluminum nitride joined body which concerns on this invention is a manufacturing method of the aluminum nitride joined body which joined the aluminum nitride sintered compacts, which opposes the said two aluminum nitride sintered bodies in which the alumina layer was formed in the joining surface from the said joining surface opposingly. And a step of bonding the aluminum nitride sintered bodies to each other by heating at a temperature of 1300 to 1700 ° C with a paste layer containing an alkaline earth metal compound interposed between the joining surfaces.

Aluminum nitride bonding body, alumina layer, paste layer

Description

Manufacturing method of aluminum nitride bonding body {PROCESS FOR PRODUCING ALUMINUM NITRIDE JOINT PRODUCT}

The present invention relates to a method for producing an aluminum nitride conjugate. In more detail, this invention relates to the manufacturing method of the aluminum nitride joined body which joined the aluminum nitride sintered compacts.

In recent years, a member made of aluminum nitride having excellent heat resistance and corrosion resistance has been used as a member such as a plate heater and an electrostatic chuck for mounting and processing a semiconductor wafer. In the production of such a member made of aluminum nitride, a small aluminum nitride sintered body is often joined to each other to produce a large member. Thereby, the member which has various shapes can also be obtained from the aluminum nitride sintered compact of a simple shape.

As a joining method of an aluminum nitride sintered compact, the following methods are known. For example, in Patent Document 1, as shown in FIG. 5, a paste 502 containing an aluminum nitride powder and a powder of rare earth oxides and / or calcium carbonate is coated on the aluminum nitride sintered body 501, and on this, After the aluminum nitride sintered body 503 was brought into close contact, a pressure of 1 to 250 kgf / cm ² was applied in the A direction, and heated to 1700 to 2000 ° C. to manufacture the aluminum nitride bonded body 500. Moreover, in patent document 2, the binder containing aluminum nitride powder, the powder of the oxide of an alkali metal or alkaline earth metal, and the powder of a rare earth oxide is used, and in the 1st process under the pressure of 5-500 kgf / cm <^2> , It heats at 1400-1650 degreeC, and it heats at 1650-1800 degreeC in the 2nd process, and joins the aluminum nitride sintered compacts.

Patent Document 1: Japanese Patent Application Laid-Open No. 11-157951

Patent Document 2: Japanese Patent Application Laid-Open No. 10-273370

[Initiation of invention]

[Problem to Solve Invention]

However, any joining method required a heating temperature about the same as the baking temperature at the time of manufacture of an aluminum nitride sintered compact, in order to obtain the joined body firmly joined. Due to the heating at this high temperature, deterioration, deformation, or the like of the aluminum nitride sintered body is feared. Moreover, in any joining method, it is necessary to apply pressure with heating, and it is complicated.

Therefore, the objective of this invention is providing the manufacturing method of the aluminum nitride joined body which can firmly join aluminum nitride sintered compacts at the comparatively low temperature under atmospheric pressure.

[Means for solving the problem]

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, it discovered that aluminum nitride sintered compacts can be firmly joined by using a specific aluminum nitride sintered compact, and came to complete this invention.

That is, the manufacturing method of the aluminum nitride conjugate which concerns on this invention,

A method for producing an aluminum nitride bonded body in which aluminum nitride sintered bodies are bonded to each other, the two nitrided aluminum nitride sintered bodies in which an alumina layer is formed on a joining surface are opposed to each other at the joining surface, and an alkaline earth metal compound is contained between the joining surfaces. It comprises a joining process of heating at the temperature of 1300-1700 degreeC in the state which interposed the paste layer, and joining the said aluminum nitride sintered compacts together.

In the joining step, a paste layer containing an alkaline earth metal compound is formed on a joint surface on which one alumina layer of the aluminum nitride sintered body is formed, and the alumina layer of the other aluminum nitride sintered body is formed on the paste layer. After attaching a joining surface, it is preferable that it is a process of heating at the temperature of 1300-1700 degreeC, and joining the said aluminum nitride sintered bodies.

It is preferable that the thickness of the alumina layer formed in the bonding surface of the said aluminum nitride sintered compact is 0.1-10 micrometers.

[Effects of the Invention]

According to the manufacturing method of the aluminum nitride joined body which concerns on this invention, aluminum nitride sintered compacts can be firmly joined at the comparatively low temperature under atmospheric pressure.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure for demonstrating the manufacturing method of the aluminum nitride joined body of this invention.

2 is a view for explaining a method for producing the aluminum nitride conjugate of the present invention.

3 is a view for explaining a method for producing the aluminum nitride conjugate of the present invention.

4 is a diagram for explaining a method for producing the aluminum nitride conjugate of the present invention.

5 is a view for explaining a conventional method for producing an aluminum nitride sintered body.

It is a photograph of the bonding interface in an example of the aluminum nitride bonding body of this invention.

It is a figure for demonstrating the measuring method of joint strength.

8 is a diagram for explaining a method for producing a joined body in an example.

It is a figure for demonstrating the manufacturing method of the joined body in an Example.

It is a figure for demonstrating the manufacturing method of the joined body in an Example.

It is a figure for demonstrating the manufacturing method of the joined body in an Example.

[Description of the code]

101... Aluminum Nitride Sintered Body

102... Joint surface

103... Alumina layer

201... Paste layer

301... Aluminum Nitride Sintered Body

302... Joint surface

303... Alumina layer

400... Aluminum nitride conjugate

401... copula

500... Aluminum nitride conjugate

501... Aluminum Nitride Sintered Body

502... Paste

503... Aluminum Nitride Sintered Body

A… Direction of pressure application

BEST MODE FOR CARRYING OUT THE INVENTION [

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The manufacturing method of the aluminum nitride joined body which concerns on this invention is a manufacturing method of the aluminum nitride joined body which joined the aluminum nitride sintered bodies, Comprising: The said aluminum nitride sintered compact in which the alumina layer was formed in the joining surface opposes at the said joining surface, And a joining step of joining the aluminum nitride sintered bodies by heating in a state where a paste layer containing an alkaline earth metal compound is interposed between the joining surfaces. Preferably, in the said joining process, the paste layer containing an alkaline earth metal compound is formed in the joining surface in which the alumina layer of one said aluminum nitride sintered compact was formed, and the said said nitriding in the other paste layer is carried out. After attaching the joining surface on which the alumina layer of the aluminum sintered compact was formed, it heats and joins the said aluminum nitride sintered compacts.

Thus, in the manufacturing method of this invention, since the alumina layer is formed in the joining surface of an aluminum nitride sintered compact, the sintered compacts can be firmly joined together at comparatively low temperature and atmospheric pressure. Moreover, the obtained joined body has high airtightness.

EMBODIMENT OF THE INVENTION Hereinafter, the manufacturing method of this invention is demonstrated more concretely, referring drawings.

First, in the said bonding process, as shown in FIG. 1, the aluminum nitride sintered compact 101 in which the alumina layer 103 was formed in the bonding surface 102 is prepared.

Although the shape of the aluminum nitride sintered body 101 is plate-shaped, in this invention, it is not limited to this, For example, it may be columnar shape, a polygonal column shape, etc. The aluminum nitride sintered body may be a hollow structure or a solid structure. What is necessary is just to select the shape of an aluminum nitride sintered compact so that the structure of a desired joined body can be obtained.

It is preferable that the relative density of the aluminum nitride sintered compact 101 is 97% or more.

In addition, the thickness of the alumina layer 103 is preferably 0.1 to 10 µm, more preferably 1 to 5 µm. If the thickness of the alumina layer is too thin, the effect of the manufacturing method of the present invention may not be obtained. If the thickness of the alumina layer is too thick, the bonding strength between the alumina layer and the aluminum nitride sintered body may be inferior.

Although the manufacturing method of the aluminum nitride sintered compact 101 in which the alumina layer 103 was formed in the joining surface 102 is not specifically limited, For example, after manufacturing an aluminum nitride sintered compact as follows, it is alumina in the surface used as a joining surface. The method of forming a layer is mentioned.

In manufacture of an aluminum nitride sintered compact, first, an organic binder is added to aluminum nitride powder, and a sintering aid, a dispersing agent, a dispersion medium, etc. are further added and mixed as needed, and a slurry or paste is manufactured.

Examples of the organic binder include butyral resins such as polyvinyl butyral and acrylic resins such as polymethacrylbutyl. This organic binder is normally used in an amount of 0.1 to 30 parts by weight, preferably 1 to 15 parts by weight, per 100 parts by weight of aluminum nitride powder.

Examples of the sintering aid include alkaline earth oxides such as CaO and SrO, Y ₂ O ₃ , CeO ₂ , Ho ₂ O ₃ , Yb ₂ O ₃ , Gd ₂ O ₃ , Nd ₂ O ₃ , Sm ₂ O ₃ , Dy ₂ O Rare earth oxides, such as ₃ , are mentioned. Of these, Y ₂ O ₃ is preferably used. In addition, a sintering aid does not necessarily need to be an oxide, For example, carbonate, nitrate, phosphate, etc. may be sufficient. This sintering aid is normally used in an amount of 0.1 to 30 parts by weight, preferably 1 to 15 parts by weight, per 100 parts by weight of aluminum nitride powder.

Glycerine compounds etc. are mentioned as a dispersing agent. This dispersant is normally used in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of aluminum nitride powder.

Ethanol etc. are mentioned as a dispersion medium. This dispersion medium is normally used in an amount of 10 to 50 parts by weight, preferably 15 to 30 parts by weight, per 100 parts by weight of aluminum nitride powder.

Next, the slurry or paste obtained as described above is molded into a desired shape. Here, it shape | molds by shaping | molding means, such as an extrusion molding method, an injection molding method, an injection molding method, a doctor blade method, specifically ,. Subsequently, the obtained molded object is degreased and then fired to produce an aluminum nitride sintered body. After the granulation of the slurry or paste by granulating the slurry or paste with a spray dryer, the granulation powder may be molded in a mold, for example, by a cold hydrostatic press method. In addition, it is preferable to perform degreasing at 450-650 degreeC in air, and it is preferable to perform baking at 1700-1900 degreeC in nitrogen atmosphere.

Moreover, you may shape | mold by the compression molding method, without using an organic binder. For example, a mixed green powder of aluminum nitride powder and sintering aid powder is produced by a single-axis molding machine to produce a caustic green body, which is press-molded at 1 to 4 t / cm ² by a CIP (cold isostatic pressure) molding machine. You may produce a molded object. In this case, the degreasing step is unnecessary, and the obtained molded body is preferably baked under the conditions described above to produce an aluminum nitride sintered body.

Moreover, in the said aluminum nitride sintered compact, you may perform the process of a roughening process, a grinding | polishing process, etc. before the alumina layer is formed in the surface used as a joining surface. Examples of the roughening treatment include etching with an alkaline aqueous solution, sand blasting, and the like. Moreover, as a grinding | polishing process, grinding | polishing using an abrasive grain, electrolytic in-process dressing grinding, etc. are mentioned.

Next, although an alumina layer is formed in the surface used as a joining surface of the obtained aluminum nitride sintered compact, it is formed by the following oxidation processes, for example. In other words, the aluminum nitride sintered body is heated in an oxygen-containing gas atmosphere to form an alumina layer on the surface.

As the oxygen-containing gas, air is the simplest, but pure oxygen gas, oxygen may be used as an inert gas (for example, rare gas such as nitrogen, carbon dioxide, argon, etc.) and / or a gas diluted with air. . It is preferable to make the oxygen concentration in an oxygen containing gas 20% or more.

The dew point of the oxygen-containing gas is preferably -25 ° C or lower, more preferably -40 ° C to -30 ° C. In order to make a dew point into the said range, what is necessary is just to dry previously the gas to be used by suitable means, such as compression and drying with a desiccant.

The heating temperature is usually 1100 to 1300 ° C, preferably 1130 to 1270 ° C, and the heating time is usually 1 to 100 hours, preferably 5 to 30 hours.

By this oxidation treatment, aluminum nitride on the surface of the aluminum nitride sintered body is oxidized to generate α-Al ₂ O ₃ , and an alumina layer is formed on the surface serving as a joining surface of the aluminum nitride sintered body. Since the weight of the aluminum nitride sintered compact increases with the production of α-Al ₂ O _3, the increase in weight due to oxidation serves as a measure of the thickness of the alumina layer. The increase in weight of 1.6 to 6.5 mg / m ² corresponds to 2 to 10 μm.

In addition, in order to form a denser alumina layer, you may use the method of Unexamined-Japanese-Patent No. 2005-159334. That is, a step of heating the aluminum nitride sintered body to a temperature higher than 300 ° C lower than the oxidation start temperature of the aluminum nitride sintered body without substantially dissolving oxygen during the temperature increase (this step is also referred to simply as a "heating step"), And contacting the desired surface of the aluminum nitride sintered body heated to a temperature lower than 300 ° C. below the oxidation start temperature of the aluminum nitride sintered body in the step, and then maintaining the temperature at a temperature higher than the oxidation start temperature of the aluminum nitride sintered body to maintain the aluminum nitride sintered body. You may use the method including the process of oxidizing the surface of and forming an alumina layer (this process is only called a "oxidation process").

Here, oxidation start temperature is 1100 degreeC under atmospheric pressure. In addition, it is preferable that the temperature which starts contact with oxygen gas is more than an oxidation start temperature from a viewpoint of obtaining a favorable alumina layer.

The alumina layer 103 may be a layer made of θ-Al ₂ O ₃ . In the case of forming a layer made of θ-Al ₂ O ₃ is used as a method of family disclosed in Japanese Patent Laid-Open Publication No. 2001-294492. Specifically, when the aluminum nitride sintered body is treated at an oxygen atmosphere of 1.0 kPa or less at a temperature of 800 to 1000 ° C. for 0.5 to 30 hours, a layer made of θ-Al ₂ O ₃ is formed.

In addition, although the case where the alumina layer 103 is formed only in the bonding surface 102 is shown in FIG. 1, the alumina layer may be formed also in surfaces other than the bonding surface 102 of the aluminum nitride sintered compact 101. Moreover, in FIG. . That is, in the aluminum nitride sintered body 101, the alumina layer 103 should just be formed in the joining surface 102 at least. In addition, in order to form the alumina layer 103 only in the bonding surface 102, a well-known method may be used.

Next, as shown in FIG. 2, in the aluminum nitride sintered body 101, a paste layer 201 containing an alkaline earth metal compound is formed on the bonding surface 102 on which the alumina layer 103 is formed.

The paste contains an alkaline earth metal compound, and preferably contains an alkaline earth metal salt or an oxide.

Examples of the alkaline earth metal salts include calcium salts such as calcium carbonate and calcium nitrate. Of these, calcium carbonate is preferred. Examples of the alkaline earth metal oxides include calcium oxide, CaO? Al ₂ O ₃ , 3CaO? Al ₂ O ₃ , and the like. These alkaline earth metal compounds may be used alone or in combination of two or more thereof.

Moreover, the said paste may contain aluminum oxide further from a viewpoint of starting reaction at low temperature, and is 40-250 weight part normally with respect to 100 weight part of alkaline earth metal compounds, Preferably it is the quantity of 50-200 weight part It is preferable to contain.

As aluminum oxide, although a particle size is small, a fine powder is preferable.

The paste may further contain a solvent, a dispersant and the like.

Terpineol etc. are mentioned as a solvent. The solvent is usually used in an amount of 10 to 90 parts by weight, preferably 30 to 80 parts by weight, per 100 parts by weight of the alkaline earth metal compound powder. When the alkaline earth metal compound and aluminum oxide are contained, the solvent is usually used in an amount of 10 to 90 parts by weight, preferably 30 to 80 parts by weight, per 100 parts by weight of the alkaline earth metal compound and aluminum oxide in total. . You may use a solvent individually or in mixture of 2 or more types.

Ethyl cellulose etc. are mentioned as a dispersing agent. This dispersing agent is normally used in an amount of 0.5 to 20 parts by weight, preferably 1 to 10 parts by weight, per 100 parts by weight of the alkaline earth metal compound powder. Dispersants may be used alone or in combination of two or more thereof.

The said paste is obtained by adding the said component to an alkaline earth metal compound as needed, and mixing these.

As a method of forming the layer which consists of said paste in the bonding surface 102, application | coating, screen printing, etc. are mentioned.

The thickness of the paste layer 201 is preferably 10 to 1000 µm, more preferably 50 to 500 µm.

Next, as shown in FIG. 3, the bonding surface 302 on which the alumina layer 303 of the aluminum nitride sintered body 301 is formed is attached to the paste layer 201. That is, the aluminum nitride sintered body 301 is excreted in the paste layer 201 so that the bonding surface 302 in which the alumina layer 303 of the aluminum nitride sintered body 301 was formed may contact. The aluminum nitride sintered compact 301 in which the alumina layer 303 is formed on the joining surface 302 is the same as that of the aluminum nitride sintered compact 101.

Finally, after the bonding surface 302 is attached to the paste layer 201, heat processing is performed. That is, the two aluminum nitride sintered bodies 101 and 301 having the alumina layers formed on the joining surfaces 102 and 302 are opposed to each other at the joining surfaces 102 and 302 and between the joining surfaces 102 and 302. The heat treatment is performed while the paste layer 201 is interposed.

Heating temperature becomes like this. Preferably it is 1200-1700 degreeC, More preferably, it is 1300-1650 degreeC. Thus, according to the manufacturing method of this invention, since the alumina layer is provided in the joining surface of an aluminum nitride sintered compact, the joined body firmly joined by heating at comparatively low temperature is obtained. Moreover, since it joins at comparatively low temperature, in the obtained joined body, the deformation | transformation of the aluminum nitride sintered compact part is not seen, either.

Argon atmosphere, nitrogen atmosphere, etc. are mentioned as an atmosphere of a heating. From a viewpoint of using an aluminum nitride sintered compact, nitrogen atmosphere is preferable.

Moreover, since the alumina layer is provided in the joining surface of an aluminum nitride sintered compact, even if heating under atmospheric pressure, aluminum nitride sintered compacts can be firmly joined, and the airtightness of the obtained joint part is also high. Moreover, in the obtained joined body, the deformation | transformation of the aluminum nitride sintered compact part produced | generated when a pressure is not applied uniformly according to the conditions of pressure application can also be suppressed. In addition, in the case of applying a pressure together with heating using a hot press sintering furnace or the like, bonding of a large sintered compact (for example, φ500 mm or more) or a complicated sintered compact is difficult, but in the production method of the present invention, such a sintered compact There is an advantage that can be easily bonded to each other.

Moreover, in the manufacturing method of this invention, a joined body is obtained by the heating under atmospheric pressure, For example, you may heat under the pressure of 0.1 MPa-300 MPa, and can obtain a joined body.

The heating time is preferably 1 to 30 hours, more preferably 3 to 10 hours.

As an apparatus used for heating, an atmospheric pressure sintering furnace, a hot press sintering furnace, and a hot isostatic press furnace are mentioned.

In this way, the aluminum nitride bonded body is obtained by the manufacturing method of the present invention, and in the present invention, as described above, the paste layer 201 may be formed only on the bonding surface 102 of the aluminum nitride sintered body 101. The paste layer may be formed on the joint surface 302 of the aluminum nitride sintered body 301 together with the joint surface 102 of the aluminum nitride sintered body 101, and both paste layers may be adhered to each other to perform heat treatment.

After the paste layer 201 is formed, the paste layer 201 is dried at a temperature of room temperature to 80 ° C., and then the bonding surface 302 on which the alumina layer 303 of the aluminum nitride sintered body 301 is formed is attached. You may have to.

As shown in FIG. 4, in the aluminum nitride bonded body 400 obtained as described above, the alumina layer is not seen at the bonded portion 401, and the aluminum nitride sintered bodies are firmly bonded to each other, and the bonded body has high airtightness. Have In addition, although the junction part was shown typically in FIG. 4, since the junction body actually obtained is firmly bonded, a bonding interface is not normally observed by a SEM photograph. This is considered to be because the following phenomenon occurs in the said bonding process. For example, when a paste containing calcium carbonate (CaCO ₃ ) is used as the paste, calcium carbonate (CaCO ₃ ) first becomes calcium oxide (CaO) by heating. Next, calcium oxide (CaO) and alumina (Al ₂ O ₃ ) present on the surface of the aluminum nitride sintered body react to form calcium aluminates such as CaO? Al ₂ O ₃ and CaO? 2Al ₂ O ₃ . Calcium aluminate diffuses into the bulk of the aluminum nitride sintered body along grain boundaries. For this reason, it is considered that an alumina layer does not exist in the junction part 401.

Similarly, in the case of using a paste containing calcium oxide (CaO), the calcium oxide (CaO) and alumina (Al ₂ O ₃ ) present on the surface of the aluminum nitride sintered body react with each other by heating, and thus calcium alumina as described above. Nate layer is produced. When a paste containing calcium oxide (CaO) and alumina is used, alumina (Al ₂ O ₃₎ present on the surface of the calcium oxide (CaO) and the alumina and aluminum nitride sintered body contained in the paste is heated by heating. ) Reacts to produce such calcium aluminate. Further, CaO? Al ₂ O _3, when using the paste containing such 3CaO? Al ₂ O ₃ also, it is believed that the calcium aluminate is produced by the same manner as with the heating. In any of these cases, the produced calcium aluminate diffuses into the bulk of the aluminum nitride sintered body along the grain boundaries, and thus, it is considered that a bonded body having no alumina layer at the junction is finally obtained.

In the present invention, the reason why the aluminum nitride sintered bodies can be firmly joined by heating at a relatively low temperature is considered as follows.

The reaction between the alkaline earth metal compound represented by calcium oxide and alumina occurs at a relatively low temperature of about 1400 ° C. It is also believed that AlN is dissolved in aluminum nitride particles on the calcium aluminate produced by the reaction with the temperature increase. The CaO-Al ₂ O ₃ -AlN produced in this way enables firm bonding of AlNs. AlN dissolved in liquid phase is reprecipitated during cooling. The liquid component of CaO-Al ₂ O ₃ diffuses into the aluminum nitride sintered body along the grain boundary and is not confirmed at the junction.

Since the aluminum nitride bonded body 400 obtained as mentioned above is manufactured by the heating at comparatively low temperature, the deformation | transformation of the junction part 401 and the aluminum nitride sintered compact parts 101 and 301 is suppressed.

Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.

1. Evaluation method

1) Evaluation of Bonding Interface

The aluminum nitride sintered-bonding interface was observed using the secondary electron scanning electron microscope (SEM).

2) joint strength

The 3-point bending test was done based on the fine ceramics room temperature bending test method (JIS C2141). The distance between points was set to 30 mm. When the aluminum nitride after joining was evaluated, the bonded body 700 obtained by joining aluminum nitride bonded bodies 702 having a thickness of 30 mm x 30 mm and a thickness of 3 mm was processed into a test piece 703 having a total length of 40 mm and a thickness of 3 mm (see FIG. 7). That is, it cut along the dotted line of FIG. Next, this test piece 703 was placed so that the junction 701 was located at the center between the points, and a load was applied from the junction 701.

3) Air tightness test

In order to evaluate the degree of joining at the joining interface, a joined body obtained by joining an aluminum nitride sintered body processed into a hollow columnar shape having a diameter of Φ50mm, a height of 30mm and a thickness of 8mm, and an aluminum nitride sintered body processed into a disk having a diameter of 50mm and a thickness of 5mm was used. A helium leak test was conducted by an Al Dr. helium leak detector (model HELIOT 704D2).

2. Aluminum nitride sintered body with an alumina layer formed on the joint surface

1) Aluminum nitride sintered body (A-1-1) to (A-1-3) having an alumina layer formed on the joint surface

The aluminum nitride sintered compact (made by Tokuyama, SH-15) of 30 mm x 30 mm and thickness 3mm was oxidized on 1200 degreeC and the conditions of 5 hours in oxygen atmosphere. An aluminum nitride sintered body (A-1-1) (hereinafter also referred to simply as an aluminum nitride sintered body (A-1-1)) in which an alumina layer having a thickness of 2 µm was formed on the surface of all surfaces including the joining surface was obtained.

Aluminum nitride sintered body (made by Tokuyama, SH-15) processed into a hollow cylindrical column of Φ50mm, height 30mm, thickness 8mm, and aluminum nitride sintered body made by a plate of Φ50mm, thickness 5mm (made by Tokuyama, SH-15) In the same manner, the oxidation treatment was performed, and aluminum nitride sintered bodies (A-1-2) and (A-1-3) (hereinafter, respectively) in which an alumina layer having a thickness of 2 μm were formed on the surfaces of all surfaces including the bonding surfaces, respectively. Only an aluminum nitride sintered body (A-1-2) and (A-1-3) are also obtained).

2) Aluminum nitride sintered body (A-2-1) to (A-2-3) having an alumina layer formed on the joint surface

The aluminum nitride sintered compact (made by Tokuyama, SH-15) of 30 mm x 30 mm and thickness 3mm was oxidized on 1200 degreeC and the conditions of 30 hours in oxygen atmosphere. An aluminum nitride sintered body (A-2-1) (hereinafter also referred to simply as an aluminum nitride sintered body (A-2-1)) in which an alumina layer having a thickness of 5 µm was formed on the surface of all surfaces including the bonding surface was obtained.

Aluminum nitride sintered body (made by Tokuyama, SH-15) processed into a hollow cylindrical column of Φ50mm, height 30mm, thickness 8mm, and aluminum nitride sintered body made by a plate of Φ50mm, thickness 5mm (made by Tokuyama, SH-15) Also in the same manner, the oxidation treatment was performed, and aluminum nitride sintered bodies (A-2-2) and (A-2-3) (hereinafter, respectively) in which an alumina layer having a thickness of 5 µm were formed on the surfaces of all surfaces including the bonding surfaces, respectively. Only aluminum nitride sintered bodies (A-2-2) and (A-2-3) were also obtained).

3) Aluminum nitride sintered body (B-1-1) to (B-1-3) having an alumina layer formed on the joint surface

The aluminum nitride sintered compact (made by Tokuyama, SH-50) of 30 mm x 30 mm and thickness 3mm was oxidized on 1200 degreeC and the conditions of 5 hours in oxygen atmosphere. An aluminum nitride sintered body (B-1-1) (hereinafter also referred to simply as an aluminum nitride sintered body (B-1-1)) in which an alumina layer having a thickness of 2 µm was formed on the surface of all surfaces including the bonding surface was obtained.

Aluminum nitride sintered body (made by Tokuyama, SH-50) processed into a hollow cylindrical column of Φ50mm, height 30mm, thickness 8mm, and aluminum nitride sintered body made by Tokuyama (made by Tokuyama, SH-50) made of Φ50mm, 5mm thick In the same manner, the oxidation treatment was performed, and aluminum nitride sintered bodies (B-1-2) and (B-1-3) (hereinafter, respectively) in which an alumina layer having a thickness of 2 μm were formed on the surfaces of all surfaces including the bonding surfaces, respectively. Only aluminum nitride sintered bodies (B-1-2) and (B-1-3) were also obtained).

4) Aluminum nitride sintered body (A-3-1) to (A-3-3) with an alumina layer formed on the joint surface

The aluminum nitride sintered compact (made by Tokuyama, SH-15) of 30 mm x 30 mm and thickness 3mm was oxidized on condition of 1100 degreeC and 2 hours in oxygen atmosphere. An aluminum nitride sintered compact (A-3-1) (hereinafter also referred to simply as an aluminum nitride sintered compact (A-3-1)) was obtained in which an alumina layer having a thickness of 0.5 µm was formed on the surfaces of all surfaces including the joining surfaces.

Aluminum nitride sintered body (made by Tokuyama, SH-15) processed into a hollow cylindrical column of Φ50mm, height 30mm, thickness 8mm, and aluminum nitride sintered body made by a plate of Φ50mm, thickness 5mm (made by Tokuyama, SH-15) Similarly, the oxidation treatment was carried out, and aluminum nitride sintered bodies (A-3-2) and (A-3-3) (hereinafter, respectively) in which an alumina layer having a thickness of 0.5 µm were formed on the surfaces of all surfaces including the bonding surfaces, respectively. Only aluminum nitride sintered bodies (A-3-2) and (A-3-3) were also obtained).

5) Aluminum nitride sintered body (A-4-1) to (A-4-3) with an alumina layer formed on the joint surface

The aluminum nitride sintered compact (made by Tokuyama, SH-15) of 30 mm x 30 mm and thickness 3mm was oxidized on condition of 1300 degreeC and 15 hours in oxygen atmosphere. An aluminum nitride sintered body (A-4-1) (hereinafter also referred to simply as an aluminum nitride sintered body (A-4-1)) in which an alumina layer having a thickness of 7 µm was formed on the surface of all surfaces including the joining surface was obtained.

Aluminum nitride sintered body (made by Tokuyama, SH-15) processed into a hollow columnar shape of Φ50mm, height 30mm, thickness 8mm and aluminum nitride sintered body made by a plate of Φ50mm, thickness 5mm (made by Tokuyama, SH-15) The aluminum nitride sintered bodies (A-4-2) and (A-4-3) (hereinafter referred to as hereinafter) were subjected to oxidation treatment in the same manner, and to form alumina layers having a thickness of 7 µm on the surfaces of all surfaces including the bonding surfaces, respectively. In each case, only aluminum nitride sintered bodies (A-4-2) and (A-4-3) were obtained.

3. Fabrication of Bonding Paste

1) Bonding paste (A)

Together with 50 g of calcium carbonate (manufactured by Wako Pure Chemical Industries Ltd.) and 50 g of alumina powder (manufactured by Showa Denko), 60 g of terpineol as a solvent and 3 g of ethyl cellulose as a dispersant were mixed using a ball mill to prepare a bonding paste (A). did.

2) Bonding paste (B)

100 g of calcium carbonate (made by Wako Pure Chemical Industries, Ltd.), 60 g of terpineol as a solvent, and 3 g of ethyl cellulose as a dispersing agent were mixed using a ball mill to prepare a bonding paste (B).

3) Bonding paste (C)

100 g of 3CaO-Al ₂ O ₃ , 60 g of terpineol as a solvent, and ₃ g of ethyl cellulose as a dispersant were mixed using a ball mill to prepare a bonding paste (C).

4) Bonding paste (D)

100 g of calcium oxide (made by Wako Pure Chemical Industries Ltd.), 60 g of terpineol as a solvent, and 3 g of ethyl cellulose as a dispersing agent were mixed using a ball mill to prepare a bonding paste (D).

Example 1-1

Bonding paste (A) was apply | coated to aluminum nitride sintered compact (A-1-1) in thickness of 300 micrometers, and another aluminum nitride sintered compact (A-1-1) was arrange | positioned to the apply | coated bonding paste (A) layer. (See Figures 8, 9). The aluminum nitride sintered compact (A-1-1) (in the state where another aluminum nitride sintered compact (A-1-1) was disposed) was dried in a constant temperature dryer maintained at 80 ° C. Subsequently, this was arrange | positioned in the jig | tool of a boron nitride, and it heated at 1600 degreeC for 5 hours in nitrogen atmosphere, and bonded aluminum nitride sintered compacts (A-1-1). Although the SEM photograph of the obtained joined body was shown in FIG. 6, it bonded together so that an interface cannot be distinguished. Moreover, as a result of the bending strength test, the same strength (340 MPa) as the aluminum nitride sintered compact before joining was shown.

Example 1-2

Bonding paste (A) was apply | coated to aluminum nitride sintered compact (A-1-2) in thickness of 300 micrometers, and aluminum nitride sintered compact (A-1-3) was arrange | positioned to the applied bonding paste (A) layer (FIG. 10). , 11). The aluminum nitride sintered compact (A-1-2) (in the state where the aluminum nitride sintered compact (A-1-3) was disposed) was dried in a constant temperature dryer maintained at 80 ° C. Subsequently, it heated on the same conditions as Example 1-1, and bonded both.

When the helium leak test was done about the obtained joined body, the leak amount was 5.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Example 2-1

Joining was performed by the method similar to Example 1-1 except having used aluminum nitride sintered compact (A-1-1), and using aluminum nitride sintered compact (B-1-1). The bending strength test of the obtained joined body showed the same strength (300 MPa) as that of the aluminum nitride sintered body before joining.

Example 2-2

Except having used aluminum nitride sintered compact (A-1-2) and (A-1-3), and using aluminum nitride sintered compact (B-1-2) and (B-1-3), it is the same as that of Example 1-2. Joining was performed by the method.

When the helium leak test was done about the obtained joined body, the leak amount was 5.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Example 3-1

Bonding was performed by the method similar to Example 1-1 except having used the aluminum nitride sintered compact (A-1-1) instead of the aluminum nitride sintered compact (A-1-1). The bending strength test of this joined body showed the same strength (350 MPa) as that of the aluminum nitride sintered body before joining.

Example 3-2

Except for using aluminum nitride sintered body (A-1-2) and (A-1-3) instead of aluminum nitride sintered body (A-2-2) and (A-2-3), the same as in Example 1-2 Joining was performed by the method.

When the helium leak test was done about the obtained joined body, the leak amount was 5.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Example 4-1

It bonded by the method similar to Example 1-1 except having used the bonding paste (B) instead of the bonding paste (A). The bending strength test of this joined body showed the same strength (330 MPa) as that of the aluminum nitride sintered body before joining.

Example 4-2

Bonding was performed by the same method as Example 1-2 except having used the bonding paste (B) instead of the bonding paste (A).

When the helium leak test was done about the obtained joined body, the leak amount was 5.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Example 5-1

It bonded by the method similar to Example 1-1 except having used the bonding paste (C) instead of the bonding paste (A). The bending strength test of this joined body showed the same strength (330 MPa) as that of the aluminum nitride sintered body before joining.

Example 5-2

Bonding was performed by the same method as Example 1-2 except having used the bonding paste (C) instead of the bonding paste (A).

When the helium leak test was done about the obtained joined body, the leak amount was 5.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Example 6-1

It bonded by the method similar to Example 1-1 except having used the bonding paste (D) instead of the bonding paste (A). The bending strength test of this joined body showed the same strength (360 MPa) as that of the aluminum nitride sintered body before joining.

Example 6-2

Bonding was performed in the same manner as in Example 1-2 except that the bonding paste D was used instead of the bonding paste A.

When the helium leak test was done about the obtained joined body, the leak amount was 5.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Example 7-1

Joining was performed by the method similar to Example 1-1 except having used aluminum nitride sintered compact (A-1-1), and using aluminum nitride sintered compact (A-3-1). The bending strength test of this joined body showed the same strength (320 MPa) as that of the aluminum nitride sintered body before joining.

Example 7-2

Except for using aluminum nitride sintered body (A-1-2) and (A-1-3) instead of aluminum nitride sintered body (A-3-2) and (A-3-3), the same as in Example 1-2 Joining was performed by the method.

When the helium leak test was done about the obtained joined body, the leak amount was 8.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Example 8-1

Bonding was performed by the method similar to Example 1-1 except having used aluminum nitride sintered compact (A-4-1) instead of aluminum nitride sintered compact (A-1-1). The bending strength test of this joined body showed the same strength (310 MPa) as that of the aluminum nitride sintered body before joining.

Example 8-2

Except having used aluminum nitride sintered compact (A-1-2) and (A-1-3), instead of aluminum nitride sintered compact (A-4-2) and (A-4-3), it carried out similarly to Example 1-2. Joining was performed by the method.

When the helium leak test was done about the obtained joined body, the leak amount was 8.0x10 <^-9> atm * cc / sec or less, and showed high airtightness.

Claims (3)

As a manufacturing method of the aluminum nitride joined body which joined the aluminum nitride sintered bodies, 1300-1700 degreeC in the state which the two said aluminum nitride sintered bodies in which the alumina layer was formed in the joining surface opposed at the said joining surface, and the paste layer containing an alkaline earth metal compound was interposed between the said joining surfaces. Bonding step of joining the aluminum nitride sintered bodies by heating at a temperature of Method for producing an aluminum nitride conjugate comprising a. The method of claim 1, The said joining process forms the paste layer containing an alkaline earth metal compound in the joint surface in which the alumina layer of one said aluminum nitride sintered compact was formed, and the alumina layer of the said another aluminum nitride sintered compact was formed in the paste layer. After attaching a joining surface, it heats at 1300-1700 degreeC and is a process of joining the said aluminum nitride sintered compacts, The manufacturing method of the aluminum nitride joined body characterized by the above-mentioned. The method according to claim 1 or 2, The manufacturing method of the aluminum nitride joined body whose thickness of the alumina layer formed in the joining surface of the said aluminum nitride sintered compact is 0.1-10 micrometers.

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