JPS6376397A - Manufacture of ceramic board - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] By stretching a film on both sides of the green sheet, it becomes possible to fill the conductive paste from both sides of the green sheet, and it becomes possible to fill the conductive paste from both sides of the green sheet. This allows reliable quality to be obtained even when the diameter of the through hole is small and the aspect ratio is high.

[Industrial application field]

The present invention relates to a method of manufacturing a ceramic substrate formed by firing a green sheet, and particularly relates to a method of manufacturing a ceramic substrate in which filling of conductive paste in a paste filling step is improved to improve quality.

Ceramic substrates used in electronic devices are generally manufactured by laminating a plurality of green sheets on which patterned wiring and the like are formed and hardening them by firing.

In recent years, such ceramic substrates have become increasingly denser due to higher density packaging of semiconductor elements and the like, and the width of the pattern wiring has been formed to be as narrow as possible.

Therefore, the vias that connect the stacked pattern wirings also naturally have a small diameter, resulting in a reduction in the quality of the vias.

Therefore, it is desired to improve the quality of such small diameter vias.

[Conventional technology]

Conventionally, manufacturing was carried out as shown in the conventional manufacturing process diagrams of FIGS. 3(a) to 3(f).

As shown in FIG. 3(a), a soft green sheet material 11 is stretched on the upper surface of the film 10 using a doctor blade 16, formed to a predetermined thickness, and dried to create a green sheet 1 by the doctor blade processing process. is formed.

This green sheet l is cut into a predetermined size as shown in (b), and after cutting, as shown in (c), a through hole 3 is formed so as to pass through the film 10 and the left side of the green sheet l.
The drilling machine that processes the material performs the processing process.

Next, as shown in (d), the conductive paste 4 is loaded on the top surface of the film 10 so that each through hole 3 is filled with the conductive paste 4, and the squeegee 12 is operated in the direction of the arrow. A paste filling process is performed in which filling is performed by this process.

After filling the conductive paste 4 in this way, as shown in (e), the film 10 is peeled off and the conductive paste 4 is applied by screen printing to form a pattern 14. As shown in f), a plurality of green sheets 1 on which patterns 14 are formed are placed in a jig 1.
A firing step is performed in which the specimens are stored in stacks 5 and 5, are pressurized by the cover plate 15A in the direction of arrow A, are inserted into a high-temperature furnace, and are fired.

In this case, the conductive paste 4 filled in the through hole 3 forms a via, which connects the stacked patterns.

[Problem that the invention seeks to solve]

In such a manufacturing method, when filling the conductive paste 4, if the diameter of the through hole 3 is extremely small with respect to the thickness T of the green sheet 1, as shown in (d), the through hole 3
The conductive paste 4 cannot be completely filled.

Therefore, when the green sheets 1 are stacked, there is a problem that in the worst case, the patterns 14 between the stacked layers become disconnected.

[Means for solving problems]

FIG. 1 is a sectional view showing the principle of the present invention.

As shown in Figure 1, a film (2) is stretched on both sides of the green sheet (1) after the doctor blade processing process,
In the paste filling process, the conductive paste (4) is filled from both sides of each side of the film (2).

By manufacturing in this way, the aforementioned problems are solved.

[For production]

That is, by stretching a film on both sides of the green sheet, the conductive paste can be filled from both sides.

Therefore, even if the diameter is small with respect to the thickness T, insufficient filling as in the conventional case can be avoided, and patterns will not be disconnected when stacked, and quality can be improved. .

〔Example〕

The present invention will be explained in detail below with reference to FIG.

FIGS. 2(a) to 2(d) are manufacturing process diagrams of an embodiment of the present invention. Like numbers refer to like objects throughout the design.

As shown in FIG. 2(a), a film 2 is stretched over both sides of the green sheet 1 formed by the doctor blade processing process.

In this case, since it is necessary to make the film 2 adhere closely to the dried green sheet 1, it is preferable to use a film made of polyvinylidene chloride material that can be bonded by thermocompression, for example. good.

In the green sheet 1 on which the film 2 is stretched on both sides in this manner, through-holes 3 are punched in a processing step, as shown in FIG. 3(b).

Next, as shown in (c), the filling of the wing body paste 4 is
Filling with the conductive paste 4 is performed from the side shown in (d), and then from the B side with the A side facing down.

Therefore, in the paste filling step, the conductive paste 4 is filled from both sides, A and B.

In addition, after the paste filling process, the film 2
Lamination and curing are performed through peeling, pattern formation, and baking processes.

In this way, in the paste filling process, when the conductive paste 4 is applied from both sides of the film 2, the through hole 3 is filled with the conductive paste 4 from both sides, so that the thickness T
Even with a high aspect ratio (T/D) where the diameter is small compared to that of the through hole 3, each through hole 3 can be sufficiently filled with the conductive paste 4.

〔Effect of the invention〕

As described above, according to the present invention, even through holes with a high aspect ratio can be sufficiently filled with conductive paste.

Therefore, compared to the past, it is possible to improve the quality and promote high-density packaging by making the pattern thinner, which has great practical effects.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the principle of the present invention. FIGS. 2(a) to 2(d) are manufacturing process diagrams of an embodiment of the present invention. FIGS. 3(a) to 3(f) show conventional manufacturing process diagrams. In the figure, 1 is the green sheet. 2 is film. 3 is a through hole. (d>

Claims (1)

[Claims] A doctor blade processing step for forming the green sheet (1), a drilling step for forming through holes (3) at predetermined locations of the green sheet (1), and a drilling step for forming through holes (3) in the through holes (3). In the method for manufacturing a ceramic substrate formed by a paste filling step of filling a conductive paste (4) and a firing step of hardening by heating at a predetermined temperature, both sides of the green sheet (1) after the doctor blade processing step A method for manufacturing a ceramic substrate, characterized in that a film (2) is stretched across the substrate, and in the paste filling step, filling of the conductive paste (4) is carried out from both sides of each side of the film (2).