JPS59132187A - Method of producing ceramic circuit board - 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 of manufacturing a ceramic wiring board.

Ceramic wiring boards generally use an alumina substrate, and conductor pastes such as gold paste, silver-palladium, and gold-platinum paste are used to form conductors. However, when a conductor is formed using such a commercially available paste, the adhesive strength of the conductor layer is 1.0 to 1.0 when an alumina substrate with an alumina purity of 96% (hereinafter referred to as 96% alumina substrate) is used. An alumina substrate with an alumina content of 99.5% (
If a 99.5% alumina substrate (hereinafter referred to as a 99.5% alumina substrate) or a SiC substrate is used, the adhesive strength is weak and a good circuit cannot be formed.

Furthermore, the solder resistance and bonding properties are also unsatisfactory.

The object of the present invention is to provide a ceramic wiring board that does not have these drawbacks.

In the present invention, 1 to 4 parts by weight of a mixed powder of Cu powder and Mn powder is placed on a ceramic substrate in 100 parts by weight of noble metal powder.

The present invention relates to a method for manufacturing a ceramic wiring board, in which a conductive paste made by adding and mixing a binder and a solvent is printed and then fired.

In the present invention, the noble metal powder is gold powder.

Silver-palladium powder, gold-platinum powder, etc. are used, and there are no particular limitations.

Although there is no particular restriction on the mixing ratio of Cu powder and Mn powder, it is preferable to mix 50 to 30% by weight of Mn powder to 50 to 70% by weight of Cu powder. A mixed powder of Cu powder and Mn powder must be used.

When using a single Cu powder, the firing temperature must be increased.

Single powder Mn powder has weak adhesive strength. It is necessary to add 1 to 4 parts by weight of the mixed powder of Cu powder and Mn powder to 100 parts by weight of the precious metal powder. If it is less than 1 part by weight, the adhesive strength will be weak, and if it exceeds 4 parts by weight, it will not form in the conductor circuit. The resistivity increases rapidly, the performance as a conductor deteriorates, and the object of the present invention cannot be achieved.

In the present invention, binders include ethyl cellulose, nitrocellulose, and acrylic resin.

Terpineol, carpitol acetate, etc. are used as the solvent for the epoxy resin, but there are no particular restrictions on the amount of these.

In addition to the above, glassy components such as lead borosilicate glass and barium borosilicate may be added to the conductor paste of the present invention, if necessary.

Furthermore, in the present invention, the ceramic substrate includes:

Although there are no particular limitations, it is particularly effective for non-oxide based substrates such as 99.5% alumina substrates and SiC.

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

Example I A mixed powder of 100 parts by weight of Au powder and Cu powder and Mn powder in the amounts shown in Table 1 (Cu powder: 60% by weight, Mn powder: 40% by weight).

Furthermore, 6 parts by weight of ethyl cellulose was used as a binder.

40 parts by weight of terpineol and 20 parts by weight of lead porosilicate glass were added as a solvent, and the mixture was uniformly mixed in a sieve machine to form a paste to obtain a conductor paste.

Next, the conductive paste obtained above was screen printed on a 96% alumina substrate, a 99.5% alumina substrate, and a SiC substrate, and then fired at 850'C.

Seven adhesive strength tests were conducted by soldering predetermined metals.

The test results are also shown in Table 1.

Example 2 Adding Cu in the amount shown in Table 2 to 100 parts by weight of silver-palladium powder
Mixed powder of powder and Mn powder (Cu powder 60% by weight.

(Mn powder 40% by weight), a conductor paste was obtained using the same formulation and method as in Example 1. Thereafter, an adhesive strength test was conducted in the same manner as in Example 1.

The test results are shown in Table 2.

Below is a margin Example 3 100 parts by weight of gold-platinum powder, Cu powder and M in the amount shown in Table 3
Mixed powder with n powder (Cu powder 60% by weight, Mn powder 40% by weight
), a conductor paste was obtained using the same formulation and method as in Example 1. Thereafter, an adhesive strength test was conducted in the same manner as in Example 1. The test results are shown in Table 3.

As shown in Tables 1, 2, and 3, by using the conductive paste of the embodiment of the present invention, 99.5%
Adhesion strength to 96% alumina substrate and SiC substrate is 1.0 to 1.5 Ky/lr.
m' can be obtained, and a good ceramic wiring board can be manufactured.

The present invention uses 100 parts by weight of noble metal powder and 1 to 4 parts by weight of a mixed powder of Cu powder and Mn powder on a ceramic substrate.

Since a conductive paste made by adding and mixing a binder and a solvent is printed and then fired, the conductive paste is 1.0 to 1.0% even for 99.5% alumina substrates and SiC substrates. s Kg/rra
A ceramic wiring board having an adhesive strength of n' and satisfactory solder resistance and bonding properties can be manufactured.

Claims (1)

[Claims] 1. On a ceramic substrate, 100 parts by weight of noble metal powder is coated with C.
1 to 4 parts by weight of mixed powder of U powder and Mn powder. A method for manufacturing a ceramic wiring board, characterized by printing a conductive paste made by adding and mixing a binder and a solvent, and then firing it.