JPH0210592B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for punching fine through holes in green sheets for ceramic multilayer substrates.

FIG. 1 shows an example of a ceramic multilayer substrate for 25 chips. This multilayer board is usually composed of the following four types of layers. What is indicated by 1 in FIG. 1 is called the surface layer, and
For example, the unit pattern An consisting of holes indicated by the intersections of grid lines as shown in FIG. 2 is A ₁ ~
The surface layer 1 as a whole has a punching pattern formed in each of the regions indicated by A ₂₅ (however, A ₁₄ to _{A 25} are not shown) and composed of a large number of identical unit patterns An. Further, those indicated by 2 to 5 in FIG. 1 are called enlarged layers, and for example, in the enlarged layer 4, there is a core portion d ₁ consisting of holes indicated by the intersections of grid lines as shown in FIG. Similarly, a unit pattern Dn consisting of an outer portion d ₀ consisting of holes indicated by intersection points is formed in each of the regions shown in D ₁ to D ₂₅ (however, D ₈ to _{D 25} are not shown) in FIG. The enlarged layer 4 as a whole has a hole pattern consisting of a large number of identical unit patterns Dn. Similarly, other expansion layers 2, 3, and 5 each have a large number of the same unit patterns.
It has a hole pattern consisting of Bn, Cn, and En (not shown). In addition, the unit pattern Bn of the expansion layer is
Cn, Dn and En are usually different from each other. What is shown in Figs. 1 6 to 17 is what is called the intermediate layer, and the hole punching patterns of these ten or so sheets are the same.
Each surface is made with holes evenly spaced vertically and horizontally. FIG. 18 shows a terminal connection layer, and the hole punching pattern is different from that of the intermediate layer, and the hole pitch is also wide.

In this way, each layer constituting the multilayer board has a different hole punching pattern, and a very large number of through holes are required. This drilling should be done in the ceramic green sheet before firing, but there are three possible processing methods: cutting with a conventional drill, electron beam processing, and punching with a punch and die. It is being

However, the cutting process using the first drill had problems in that the processing speed was slow and the tool life was short.

Further, electron beam processing has the disadvantage that the equipment is extremely expensive. As for the punch and die punching method, it is possible to first create a mold by combining the punch and die with the pattern shown in Figure 1, and then punch it out in one process. There were disadvantages in that it required manufacturing, and in cases where the hole spacing was narrow, it was difficult to manufacture the mold.

Another possible method for punching and punching using a punch and die is to move a pair of punches and dies vertically and horizontally to process all the patterns shown in Figure 1, but this method suffers from the problem of slow processing speed. be.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for punching holes in ceramic green sheets for multilayer substrates that is inexpensive and highly productive, eliminating the drawbacks of the prior art described above.

That is, the present invention focuses on the fact that the hole punching pattern of a multilayer board, especially for the surface layer and enlarged layer, is a repeating pattern of unit patterns for each LSI chip mounted on the top of the board in the surface layer. On the other hand, by adopting a mold structure that allocates one set of punch and die, it has become possible to punch holes in all layers with high efficiency using two to three types of molds.

Hereinafter, the present invention will be explained in detail based on an embodiment shown in FIGS. 4 to 7.

FIG. 4 is an overall view of the processing apparatus, FIG. 5 is a schematic view of the lower mold, FIG. 6 is a schematic view of the upper mold, and FIG. 7 is a schematic diagram showing the state of holding and feeding the green sheet.

In FIGS. 3 to 7, 19 is a die piece, the number of die holes 20 is equal to the number of chips mounted on the board, and the pitch is the same as the pitch between repeated unit patterns on the surface layer (P in FIG. 1). _L )
It is equal to .

Further, as shown in FIGS. 6a and 6b, reference numeral 21 denotes a punch, which is arranged in the same number and at the same pitch as the die holes 20 formed in the die piece 19. 33 is the upper die set plate, 34 is the stripper plate, 36
3 is a sub-guide post that guides the stripper plate 34; 37 is a punch plate that supports the punch 21 together with the bucking plate 38;
9 is a guide hole into which the guide post 35 of the die set is inserted, and 40 is a spring that presses the stripper plate 34.

As shown in Fig. 7a and b, the green sheet 22
is fixed to a frame-shaped holder 23 with adhesive or the like, and the holder 23 is positioned on the arm 25 by a pin 24. This arm 25 is
- It is connected to the Y drive device 26 and can be positioned at a commanded position using an NC tape or the like.

Furthermore, as shown in FIGS. 5a and 5b, the die piece 19
is fitted into the die plate 27, but when the thickness of the frame of the holder 23 is t _{p and the thickness of the arm 25 is t A ,} the relationship between the die surface 30 and the die plate surface 29 is t _p +t _A This step allows the green sheet 22 to move smoothly on the die plate surface 29 when the arm 25 slides on the die plate surface 29. The die plate 27 is positioned and fastened to the lower die set plate 28.

The lower die set plate 28 is fixed to the press bolster 31, and the upper die set plate 3
3 is fixed to the ram 32.

In the above configuration, the green sheet 22 is moved through the frame 23 and the arm 25 to the X-Y drive device 26.
For example, punch 21-1 and die hole 2.
When the unit pattern 41 of the surface layer 1 in FIG. 1 is processed using the punch 21-8, for example,
Pattern A _B can also be processed using die hole 20-8. On the other hand, for the enlarged layer, the same type of punch 21-1 and die hole 20-1 are used to process the green sheets in order so that one unit pattern B ₁ to _{E 1} can be processed. Some similar unit pattern Bn~
En can be processed.

Regarding the intermediate layer, since the pitch P _L of the punch and die pair is usually an integral multiple of the hole pitch P _H (not shown) in the intermediate layer, the green sheet 22 is positioned by hole pitch P _H using the same die. If you do this, you can process it using the same method.

The conditions for the terminal connection layer are also the same as for the intermediate layer.

Note that the hole diameter of the ceramic multilayer substrate is not necessarily limited to one type, but the unit pattern An of the surface layer 1 is
and each unit pattern of enlarged layers 2 to 5
There are at most two to three types of core parts, outer shell parts, intermediate layers, and terminal connection layers that constitute Bn to En. Therefore, by preparing molds for different hole diameters, it is possible to drill holes in multilayer substrates with various patterns with high efficiency.

As described above, according to the present invention, it is possible to accommodate a large number of punched parts (holes machined by punches and dies) in a mold according to the number of chips, so that the number of holes machined per one stroke of the press is By increasing the number of holes, it is possible to drill a large number of holes without increasing the number of press strokes per minute, and by matching one punch and die hole to one chip, There is plenty of space between the punches and between the dies, making it easy to make molds, and it is also possible to accommodate different hole patterns depending on the layer of the board by X-Y driving of the green sheet. This has the effect of significantly improving processing efficiency and simplifying equipment.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of the product processed by the present invention, Figure 2
The figure is an enlarged view showing a unit pattern provided on the surface layer, FIG. 3 is an enlarged view showing an example of a unit pattern provided on the enlarged layer, and FIG. A schematic configuration diagram showing an embodiment of the apparatus for carrying out the processing method, FIG. 5a is a plan view of the lower mold shown in FIG. 4, FIG. 5b is a side view of FIG. 5a, and FIG. 6a is a Plan view of the upper mold shown in Fig. 4, No. 6
Figure b is a side view of Figure 6a, Figure 7a is a plan view showing the green sheet holding device shown in Figure 4;
Figure b is a side view of Figure 7a. Explanation of symbols 1 to 18... Ceramic substrate, 1
9...Die, 21...Punch, 22...Green sheet, 23...Holder, 25...Arm, 26
...X-Y drive device.

Claims (1)

[Claims] 1. In a method for punching holes in a green sheet for a multilayer board having a hole punching pattern in which the same unit pattern is repeated at a predetermined pitch, a plate on which a plurality of punches are fixed at the same pitch as the predetermined pitch and the fixing of the punches are used. A holder to which the green sheet is fixed is placed between a die piece having a plurality of die holes corresponding to each installation position, and an X-Y drive device moves the green sheet into the units through the holder. Holes are repeatedly punched using the punch and the die hole while moving each predetermined hole pitch in the pattern, and a plurality of holes are simultaneously punched in the unit pattern on the green sheet at the predetermined pitch. A method for punching holes in green sheets for multilayer boards.