JPH01273389A - Manufacture of ceramic multilayer interconnection substrate - Google Patents

Abstract

PURPOSE:To prevent the missing of conductor paste filled into a via hole, and to obviate the defective continuity of the via hole by laminating the insulator sheet of the next layer to an insulator sheet, on which conductor paste is printed, and printing conductor paste. CONSTITUTION:A second insulator sheet 1b is laminated onto a first insulator sheet 1a, on which a wiring conductor 2a is formed, while connecting the conductor 2a on the sheet 1a and a via hole 3 shaped to the sheet 1b. Conductor paste is printed into the hole 3 formed to the sheet 1b. Laminating and printing are repeated as required, thus acquiring the laminate of specified insulator sheets. The laminate is thermocompression-bonded again, and baked, thus obtaining a ceramic multilayer interconnection substrate. Accordingly, the missing of conductor paste filled into the hole 3 is prevented, and the defective continuity of the hole 3 is obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a ceramic multilayer wiring board, and particularly to printing conductive paste on holes and laminating insulating sheets.

[Conventional technology]

Conventionally, the manufacturing method for this type of ceramic multilayer wiring board is as follows:
As shown in FIGS. 3(a) to 3(d), insulating sheets 1d were laminated all at once and fired.

[Problem to be solved by the invention]

In the above-described conventional method for manufacturing a ceramic multilayer wiring board, a conductive paste is individually printed on each insulating sheet.

Therefore, as shown in FIG. 4, after filling the via hole with the conductive paste 2b, the insulating sheet 1d is placed on the printing table 5.
When removing the bulk, the conductive paste 2b adheres to the printing table 5, and the conductive paste 2b inside the via hole is missing. For this reason, there is a drawback that the filling of the conductive paste into the via hole becomes insufficient, resulting in poor conduction in the via hole.

An object of the present invention is to provide a method for manufacturing a ceramic multilayer wiring board that eliminates the loss of the conductive paste filled in the via holes formed in an insulating sheet and prevents conduction defects in the via holes.

[Means to solve the problem]

The method for manufacturing a ceramic multilayer wiring board of the present invention is a method for manufacturing a ceramic multilayer wiring board obtained by laminating and firing a plurality of insulator sheets in which wiring conductors and via holes are formed at predetermined positions. first formed
A second insulator sheet is laminated on the insulator sheet by connecting the wiring conductor of the first insulator sheet and the via hole formed in the second insulator sheet. The method includes a step of printing a conductive paste in the formed via hole.

〔Example〕

Next, the present invention will be explained with reference to the drawings. FIGS. 1(a) to 1(d) are cross-sectional views of a multilayer wiring board shown in order of steps to explain an embodiment of the present invention. Insulator sheet, LA, LB are alumina powder, glass powder, solvent,
This is a ceramic green sheet with a thickness of 80 μm, which is made by slip-casting a slurry mixed with an organic binder in a container and dried. The conductor paste 2a is made by uniformly dispersing metal powder containing 85% by weight of silver and 15% by weight of palladium in an organic vehicle.

After printing the conductor paste 2a on the insulator sheet 1a, φ
Insulator sheet 1b with 0.25mm via hole punched
The conductor paste 2b is printed on the conductive paste 2b after stacking them by thermocompression bonding at a temperature of 100° C. and a pressure of 50 kg/cm2.

Thereafter, lamination and printing are repeated as necessary to obtain a predetermined laminate of insulating sheets. Next, this laminate is thermocompressed again at a temperature of 100 DEG C. and a pressure of 300 kg/cm<2>, and then fired at 800 to 900 DEG C. to obtain a ceramic multilayer wiring board.

Table 1 shows the conductivity of via holes in ceramic multilayer wiring boards obtained by the conventional manufacturing method and the manufacturing method of this example.

The insulator sheets shown in Table 1 have 20 layers, and the via holes are located at the same position in each insulator sheet, connecting the upper and lower surfaces of the ceramic multilayer wiring board. The conductivity was measured when there was conduction in the via hole between both sides of the ceramic multilayer wiring board, and was measured for 1000 via holes connecting both sides of the ceramic multilayer wiring board.

FIG. 2 is a sectional view of a ceramic multilayer wiring board formed according to another embodiment of the present invention. The insulator sheet 1c is a ceramic sheet having a thickness of 100 μm, which is obtained by forming a via hole 3 of φ0.25+u+ in a ceramic green sheet and then firing it.

This insulating sheet IC is bonded and laminated using glass paste 4, but every time one layer is laminated, conductor paste 2a
Fill the via holes and print the wiring. The thus obtained laminate is refired at 400° C. to be integrated.

In this embodiment, the via holes are filled with paste after lamination, so even if the glass paste 4 is present between the insulating sheets IC, the conductive paste 2a passes through the via holes 3 during printing and is placed on the insulating sheet below. Upper conductor paste 2b
By contacting with, conduction of the via hole is ensured.

Table 2 shows the conductivity of via holes in ceramic multilayer wiring boards obtained by the conventional manufacturing method and the manufacturing method of this example.

The insulating sheet in Table 2 has 20 layers, and the structure of the via holes is the same as in the first example. be.

〔Effect of the invention〕

As explained above, in the present invention, by printing the conductive paste after laminating the next layer of insulating sheets on the insulating sheet printed with the conductive paste, there is no loss of the conductive paste filled in the via hole. This has the effect of preventing conduction defects in via holes.

FIGS. 1(a) to (d) are cross-sectional views of a ceramic multilayer wiring board shown in order of process to explain one embodiment of the present invention, and FIG. 2 is a cross-sectional view of a ceramic multilayer wiring board formed according to another embodiment of the present invention. 3(a) to 3(d) are cross-sectional views of each process for explaining a conventional method of manufacturing a ceramic multilayer wiring board, and FIG. 4 is a sectional view of FIG. 3(c). FIG. 2 is a partially enlarged view of FIG.

1a, lb, lc, ld - insulator sheet, 2a.

2b, 2c...conductor paste, 3...via hole,
4...Glass paste, 5...Printing table.

Claims (1)

[Claims] In a method for manufacturing a ceramic multilayer wiring board obtained by laminating and firing a plurality of insulating sheets in which wiring conductors and via holes are formed at predetermined positions, on a first insulating sheet in which wiring conductors are formed, the second insulator sheet to the first
connecting and stacking the wiring conductor of the insulator sheet and the via hole formed in the second insulator sheet, and printing a conductive paste in the via hole formed in the second insulator sheet. A method for manufacturing a ceramic multilayer wiring board, characterized in that: