JPS6183693A - Manufacture of metallized powder for ceramics - 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 (Field of Industrial Application) The present invention relates to a method for producing metallized powder for ceramics that provides a metallized layer that is dense, has high adhesive strength to ceramics, and has a smooth surface.

In order to form fine wiring or attach various parts to the surface of ceramic substrates used for semiconductor integrated circuit boards, electronic circuit boards, etc., a metallized layer with high adhesion strength to the ceramic and a dense and smooth surface is required. is necessary.

(Prior art and its problems) As a method of forming such a metallized layer, MO+
Mo-FJH metallization method, W metallization method, Ag.

There is a thick film method using a thick film paste made by mixing noble metal powder such as Pd or Au with glass powder. In these methods, Mo, W, Ag, Pd,
It is common to add Mn, an inorganic binder powder such as glass powder, an organic binder, and a solvent to a metal powder such as Au, and use the mixture as a paste using a milling machine or a three-roll mill.

However, since pasting is done under high viscosity conditions,
It is difficult to sufficiently convert the aggregated powder into primary particles, and it is also difficult to obtain uniform mixing and dispersion of the metal powder and the inorganic binder powder having different hardness and specific gravity 9 particle size. If a metallized layer is formed using such a paste with insufficient mixing and dispersion, a metallized layer that is dense and has a smooth surface cannot be obtained, and the adhesive strength is also low.

There was a drawback that the variation also increased.

(Objective of the Invention) The object of the present invention is to solve the above-mentioned drawbacks of the prior art. 1) Metal powder and inorganic binder powder are thoroughly disintegrated into single particles in an organic binder solution, and these powders are uniformly disintegrated. The present invention provides a method for producing dispersed metallized powder for ceramics.

(Structure of the Invention) The present invention provides a method for producing metallized powder for ceramics, which involves mixing metal powder, inorganic binder powder, organic binder, and solvent. The viscosity of the mixed mixture is below the level that does not prevent disintegration of the metal powder and inorganic binder powder, and an amount of organic binder is added and mixed to prevent the disintegrated particles from coming into direct contact with each other. The present invention relates to a method for producing metallized powder for ceramics, which comprises disintegrating inorganic binder powder into single particles, removing the solvent, and coating the surfaces of the metal powder and inorganic binder powder with an organic binder.

In the present invention, 1. The metal powder 7 is a high melting point metal powder such as Mo or W, or a noble metal powder such as Ag, Pd or Au.

Powders of base metals such as Cu and Ni are used, and there are no particular restrictions, but it is preferable to use powders of relatively hard and low-ductility high-melting metals such as Mo and W. Inorganic binder powders include Mn powder, oxides such as alumina, silica, magnesia, and calcia, glass powders made of one or more of these oxides, and silicic acid-based powders.

Zinc-lead glass may be used without any particular limitation.

The selection may be made depending on the type of metal powder used and the type of ceramic used to form the entire metallized layer.

In the present invention, as the organic binder, ethyl cellulose, nitrocellulose, acrylic resin ML "tyral resin, etc. are used, and if necessary, phthalate ester,
A plasticizer such as triethylene glycol may also be added. Ethyl acetate as the solvent.

Butyl acetate, trichlorethylene, toluene.

One or more mixed solvents such as xylene, methyl ethyl ketone, ethanol, and methanol are used.

The viscosity of the mixture of metal powder, inorganic binder powder, organic binder, and solvent is preferably 20P (voids) at maximum, and more preferably in the range of IP to 5P. The amount of organic binder added is preferably 0.5 to 6 parts by weight, and 1.0 to 6 parts by weight per 100 parts by weight of metal powder.
If it is 4.0 parts by weight, it is more preferable.

(Example) The present invention will be explained below with reference to Examples.

Example 1 Mo powder 10 with an average particle size of 0.63μIn as metal powder
0 parts by weight, average particle size 1.5 as inorganic binder powder
1.0 parts by weight of μm Mn powder and alumina.

Glass powder consisting of silica, magneua and karunua3.
0 parts by weight, 2 parts by weight of ethyl cellulose and 2 parts by weight of nitroheptylulose as an organic binder, and 200 parts of a 1:1 mixed solvent of ethyl acetate and toluene as a solvent, and these were heated in a T-ball mill for 20 hours. The metal powder and the binder powder are thoroughly disintegrated into single particles to obtain a uniformly dispersed slurry with a viscosity of 2.5 P. Next, the slurry is heated in a sieve machine. The mixture was dried while being mixed, and the solvent was removed to obtain a metallized powder for ceramics.

△ Next, terpineol f 4 was added as a solvent to 108 parts by weight of the ceramic metallized powder △ obtained above.
After adding 0 parts by weight, the mixture was mixed for 2 hours using a mulch mill, and then made into a paste using a three-roll mill. The paste obtained is S
Screen printing was performed on an iC substrate (manufactured by Hitachi Seisakusho, trade name: SC-101), and then baked at 1300° C. in a weakly reducing atmosphere to form a metallized layer on the SiC substrate. The surface roughness of the obtained metallized layer was 3.0 μmRz, and the adhesive strength with the 8iC substrate was 4.0 kg f /nIDT2 or more.

On the other hand, as a comparative example, 100 parts by weight of the Mo powder used in Example 1,
1 part by weight and 3 parts by weight of n powder and glass powder, respectively.
2 parts by weight of ethyl cellulose and 2 parts by weight of nitrocellulose as organic binders, 40 parts of terpineol as a solvent
Parts by weight were weighed, the dough was mixed for 5 hours using a sieve machine, and then the metal powder and the inorganic binder powder were made into a paste using a three-roll mill without being disintegrated into single particles. Using the obtained paste, a metallized layer was formed on a SiC substrate (manufactured by Hitachi Seisakusho, trade name 5C-101) through the same steps as in Example 1. The surface roughness of the obtained metallized layer was 6
The adhesive strength between μmRz and rough<, SiC substrate is ZOkgf
/-, which was lower than that of Example 1, and the variation was large.

Example 2 Average particle size as metal powder: 1.2 parts by weight (100 parts by weight of DW powder, 1.0 parts by weight of the glass powder used in Example 1 as inorganic binder powder, 13 parts by weight of ethyl cellulose as organic binder) Weighed out 1 part by weight of nitrocellulose and 150x parts of a 1:1 mixed solvent of ethyl acetate and toluene as a solvent, and mixed and disintegrated them in the same manner as in Example 1 to obtain a uniformly dispersed viscosity. A slurry of 4.0 P was obtained. Next, the slurry was dried in the same manner as in Example 1 to obtain a ceramic-containing metallized powder for ivy.

Furthermore, to 102 parts by weight of the memerize powder for ceramics obtained above, 3si of terpineol was added as a solvent.
A paste was prepared in the same manner as in Example 1 by adding n parts.

On the other hand, alumina 96: was placed, 1.5 parts by weight of magnesia powder as a sintering aid, 2.5 parts by weight of silica, 6 parts of butyral resin as an organic binder, and 3 parts by weight of butylbenzyl phthalate as a plasticizer. 40 parts by weight of an azeotrope of ethanol and trichlorethylene:,' and o were added as a solvent and mixed in a ball mill for 24 hours, followed by tape casting to obtain a ceramic green sheet.

The paste obtained above was printed on the obtained ceramic green sheet and fired at 1,540° C. in a slightly reducing atmosphere to form a metallized layer on the alumina ceramics. The surface roughness of the obtained metallized layer was 2.5 μmHz, and the adhesive strength with the alumina ceramic was 7.0 kg f /m.
m” or more.

On the other hand, as a comparative example, for 100 parts by weight of the W powder used in Example 2, the glass powder type 1 part used in Example 1, 1 part by weight of ethyl cellulose as an organic binder, 11 parts of nitrocellulose and a solvent were added. 351 parts of terpineol was weighed out and mixed in a sieve machine for 5 hours, and the metal powder and inorganic binder powder were made into a paste with three rolls without being granulated into single particles.

The obtained paste was subjected to the same steps as in Example 2 to form a metallized layer on alumina ceramics. The surface roughness of the obtained metallized layer was as rough as 7 μmRz, and the adhesive strength with the alumina ceramic was as low as 2.5 to 9 f/m[lI2, with large variations.

In the embodiments of the present invention, the mixture was explained using a ball mill, but the same effect can be obtained by using a miller or other mixing method.

(Effects of the Invention) According to the present invention, the viscosity of the mixture of metal powder, inorganic binder powder, organic binder and solvent is below a level that does not hinder the disintegration of the metal powder and inorganic binder powder.

Add and mix an organic binder that prevents the disintegrated particles from coming into direct contact, disintegrate the metal powder and inorganic binder powder until they become single particles, and then remove the solvent to form the metal powder. Since the surface of the inorganic binder powder is coated with an organic binder, it is possible to produce a metallized powder for ceramics that is dense, has high adhesive strength to ceramics, and provides a metalized layer with a smooth surface.

Engineering 9 possible j4> Agent Patent attorney Kunihiko Wakabayashi, -X-j9...]
・-1; No. 1゛

Claims (1)

[Claims] 1. In a method for producing metallized powder for ceramics in which metal powder, inorganic binder powder, organic binder and solvent are mixed, the viscosity of the mixture of metal powder, inorganic binder powder, organic binder and solvent is The metal powder and inorganic binder powder are made into single particles by adding and mixing an amount of organic binder that does not interfere with the disintegration of the powder and the inorganic binder powder, and in an amount that prevents direct contact between the disintegrated particles. 1. A method for producing metallized powder for ceramics, which comprises disintegrating the powder until it becomes granulated, then removing the solvent, and coating the surfaces of the metal powder and inorganic binder powder with an organic binder.