JPH05862A - Nitride ceramic metallized composition - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a metallized composition of a nitride-based ceramic body capable of ensuring high bonding strength between the nitride-based ceramic body and the metallized layer. [Structure] When a metal member 3 is bonded to a nitride-based ceramic body 1 (for example, Si ₃ N ₄ or AlN) and the metal member 3 is bonded via the metallized layer 2, the metallized layer 2 is used.
The metallization composition for forming
At least one selected from Mo and Mn and AlN are contained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nitride ceramic body metallized composition for joining a nitride ceramic body and a metal member, or for forming a conductor on the nitride ceramic body.

[0002]

2. Description of the Related Art Conventionally, for example, when a ceramic body is joined to a metal member or a conductor is formed on a nitride ceramic body, the surface of the ceramic body is metallized.

As such a metallizing method, for example, in the case of oxide ceramics such as Al ₂ O _3, metal is conventionally formed into ultrafine particles active in a high vacuum by a vapor deposition method and then is applied to the surface of the ceramic body. A method of physically depositing, or forming a metallized composition containing, for example, Mo powder and Mn powder into a paste using a binder made of an appropriate binder and a solvent, and applying this to the surface of a ceramic body A method of forming a metallized layer by firing in a weakly acidic hydrogen atmosphere containing water vapor or a mixed atmosphere of hydrogen and nitrogen is used.

By the way, the joining of the ceramic material with the metallized layer or the metal member plays an extremely important role in the composite industrial technology of both materials, and particularly Si ₃ N ₄ (silicon nitride) and AlN which are excellent in high temperature characteristics and strength. Now that the field of application of nitride-based ceramic bodies obtained by sintering nitride such as (aluminum nitride) is expanding, there is an interest in the joining technology between the nitride-based ceramic body and the metallized layer or metal member. ..

[0005]

Problems to be Solved by the Invention However, Al
_{Even if the} metallized composition used for oxide ceramics such as ₂ O ₃ is applied to the nitride ceramic body, the bonding strength between the nitride ceramic body and the metallized layer is small, and practical bonding strength is obtained. There was a problem that I could not.

[0006]

In view of the above situation, the inventors of the present invention have conducted various researches and experiments on bonding a metallized layer to a nitride ceramic body, and as a result, have found that a metallized composition containing a refractory metal and AlN. It was discovered that high bonding strength could be obtained by using, and the present invention was completed.
That is, the present invention resides in a metallized composition for a nitride-based ceramic body, which contains AlN and at least one selected from refractory metals W, Mo and Mn.

The metallized layer formed of the metallized composition of the present invention is plated by a conventional method and then a metal member to be joined is brazed to be used as a structural material or an electrically conductive metal. Has a wide range of applications, such as plating to form a conductor wiring such as a printed circuit board and applying it to an electrical material, and further using the metallized layer itself as a conductor. In a preferred embodiment, the peel strength between the metallized layer formed of the metallized composition of the present invention and the nitride ceramic body is 75 MPa (megapascal).
It is over.

The structure of the present invention will be described in detail below. The metallized composition of the present invention, that is, the metallized composition containing at least one selected from W, Mo and Mn which are refractory metals and AlN which constitutes the oxynitride glass is a nitride ceramic by coating or printing. It is used by fixing it on the body. Si ₃ is used as the nitride ceramic body.
N ₄ (silicon nitride) and AlN (aluminum nitride) sintered bodies are mentioned, and when they are industrially sintered, they are used as a sintering aid to oxidize elements of Groups 2a and 3a of the periodic table, Al and Si. The above-mentioned sintering aids, when used alone or in combination, each contain an amount of about 10% by weight as an auxiliary agent to ensure good sintering. It is composed of a nitride glass or an oxynitride crystal phase crystallized from this glass.

The oxynitride glass used here is one that is chemically similar to the oxynitride glass and the nitride constituting the intergranular phase in the above-mentioned nitride ceramic body. It is not necessary to limit the composition in particular, and MgO, AlN, Y ₂ O ₃ , SiO _{2 and the} like described below are merely examples, and at least AlN may be contained. This oxynitride glass, which has fluidity at the baking temperature, is optimal because it can adopt a simple fixing method such as coating and printing. Furthermore, this oxynitride glass does not have to be a pure glass that does not contain any crystalline material. It does not matter if you include it.

On the other hand, the refractory metal powders are W, Mo and Mn.
It is at least one selected from the following, and these are basically metal powders that do not melt or vaporize at the baking temperature,
When sintered, it exists as a metal, its silicide, carbide, or a mixture thereof. The mixing ratio with the oxynitride glass is not particularly limited, but is usually 93 parts by weight of the high melting point metal powder with respect to 7 to 50 parts by weight of the glass powder.
The range is up to 50 parts by weight.

As a method for fixing the metallized composition on the nitride ceramic body, the frit-like metallized composition as described above is applied or printed to a thickness of 0.01 to 0. Although it is most desirable to apply a layer of about 1 mm, other techniques such as spraying can also be adopted. For sintering the metallized composition to be layered, it depends on the content of the composition, but it is 1000 to 1
It may be reduced at 500 ° C or sintered in a neutral gas. On the obtained metallized layer, a metal member to be bonded is brazed as described above to form a structural material, or Au--S.
A metal having a high conductivity such as an i alloy is plated, or a conductor wiring such as a printed circuit board is formed by using the metallized layer itself as a conductor and applied to an electric material.

[0012]

The function of AlN in the metallized composition is extremely high with respect to the oxynitride glass or the oxynitride crystal phase constituting the nitride crystal or the intergranular phase of the nitride ceramic body. Guarantees a strong chemical bond strength between the nitride-based ceramic body and the metallized layer, while the refractory metal powder is present in the metallized layer as a metal, a silicide, a carbide or a mixture thereof when sintered at a high temperature. Since the wettability with the metal member to be bonded is good, the metal member can be directly bonded onto the metallized layer to obtain high bonding strength. If necessary, electrolytic or electroless plating may be further applied to the metallized layer and a metal member may be joined to the metallized layer by soldering or brazing, so that the joining strength is further enhanced, and therefore its adoption is desired.

[0013]

EXAMPLE FIG. 1 is a partial vertical cross-sectional perspective view of a joining structure using the metallized composition of the present invention. In the figure, the metallized composition fixed over the area necessary for bonding on the nitride-based ceramic body 1 forms a metallized layer 2 by sintering, and as an example, on this metallized layer 2, kovar metal (KOVAR) is used. The metal member 3 made of silver is bonded through the silver wire 4 (BAg-8). The plating of the silver braze 4 was carried out by melting at a temperature of about 850 ° C. in an atmosphere in which an ammonia decomposition gas was introduced as a wet gas (containing water vapor).

A method of measuring the bonding strength after brazing, which will be described later, will be described with reference to FIG.

The nitride ceramic body 1, which is the test piece S, is firmly fixed in a state in which a compression force (marked in bold) is applied in the central direction by a vise 8 from the left and right, and is suspended on the metal member 3. 5 is fixed with solder 6, and a push-pull gauge (spring balance) 7 is attached to the upper end of the suspension fitting 5. In this state, the hanging metal fitting 5 is pulled upward at a speed of 30 mm / min, and the strength at the moment when the metallized layer 2 is separated from the nitride-based ceramic body 1 is read by the gauge 7.

Next, specific examples of the present invention will be described.

(Example 1) (a) Nitride-based ceramic body: MgO 3% by weight, A
an Si ₃ N ₄ ceramic material containing 7% by weight of 1 ₂ O ₃ as a sintering aid was fired in an N ₂ atmosphere at 1650 ° C.
The joint surface was ground with a No. 250 diamond wheel to prepare a test piece.

(B) Oxynitride glass: 18% by weight of MgO, 20% by weight of AlN and 62% by weight of SiO ₂ were mixed and prepared, and heated in a SiC crucible coated with hexagonal BN at 1500 ° C. for 3 hours to obtain N. ₂ Gas was sent and cooled in the crucible. Obtained Mg-Al-Si-O-N
As a result of X-ray diffraction from the glass of the system, weak diffraction lines which are considered to be various SIALONs such as Si ₂ N ₂ O were recognized. The cullet thus obtained was roughly crushed in a mortar and then adjusted to have a particle size of 325 mesh or less by a vibration mill.

(C) Refractory metal powder: W powder having a purity of 99% and an average particle size of 3 μm was prepared.

(D) Fixing and Sintering: The oxynitride glass prepared as described above and W powder were mixed to form a paste, and this paste was applied on a nitride ceramic body to a thickness of 20 μm and 4 mm ² Was applied over the above area and baked in an N ₂ atmosphere at 1350 ° C. for 1 hour to obtain a metallized layer.

(E) Bonding: Ni electroless plating was applied to the metallized layer, and a hanging metal fitting for the peeling strength test was soldered to measure the peeling strength between the metallized layer and the nitride-based ceramic body. The test was performed on 20 test pieces, the average strength was 80 MPa, and the variation was δ _n-1.
= 5 MPa.

(Examples 2 to 6) The Si ₃ N ₄ ceramic body of (Example 1) and the AlN ceramic body of (Example 2) were replaced with sintering aids and refractory metal powders. Those are shown in (Examples 3 to 6), and the contents of (Examples 1 to 6) are collectively shown in Tables 1 and 2.

[0023]

[Table 1]

[0024]

[Table 2]

As can be seen from Table 2, the metallization strength for both the Si ₃ N ₄ and AlN nitride ceramic bodies is extremely high, about 70 to 80 MPa, and the strength after brazing is about 60 to 75 MPa, which is considerable. The effectiveness of the present invention was confirmed here, showing a high value.

[0026]

The nitride ceramic body metallized composition of the present invention contains at least one of refractory metals selected from W, Mo and Mn and AlN. It is possible to exhibit an excellent effect that a high bonding strength between the metallized layer and the metallized layer can be guaranteed.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional perspective view of a joining structure using a metallized composition of the present invention.

FIG. 2 is an explanatory diagram showing an outline of a strength measurement test when a metal member is brazed on a metallized layer.

[Explanation of symbols]

 1 Nitride Ceramic Body 2 Metallized Layer 3 Metal Member

Claims (1)

Claims: What is claimed is: 1. A metallized composition of a nitride-based ceramic body containing AlN and at least one selected from refractory metals of W, Mo and Mn.