JPH0415636B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a multilayer ceramic substrate formed by laminating a plurality of ceramic sheets, and is particularly characterized by the identification given to the ceramic sheets. The present invention relates to a multilayer ceramic substrate having a multilayer ceramic substrate.

[Prior art]

Ceramic substrates are widely used as wiring boards for integrated circuit modules. As the degree of integration of wiring boards increases, there is a remarkable trend toward multilayer ceramic substrates. Multilayer ceramic substrates typically consist of a stack of ceramic sheets on which conductor patterns are printed. Each ceramic sheet constituting the ceramic substrate is processed by drilling or punching through holes, filling the through holes with conductive paste, and printing conductive circuit patterns at appropriate locations on the surface of the sheet. The treated sheets are then stacked, pressed, contour cut, and sintered to form a multilayer ceramic substrate.
On the other hand, due to changes in the manufacturing process, changes in logic, etc., it may be necessary to add or delete through-hole positions, conductor wiring patterns, for each sheet or for all sheets at the same time. In such cases, leaving an identification display of the change history of through-hole information and conductor pattern information for each sheet in the board area is an effective means of showing that the changes are correctly reflected in the manufacturing process. It is.

[Problem that the invention seeks to solve]

Conventionally, the identification of the change history was typically displayed only on the top layer sheet, for example, in alphanumeric characters, but this had the disadvantage that the history of each sheet was insufficiently identified when the ceramic substrate was completed. be. Further, even in the case where the history is identified on a sheet-by-sheet basis, since the history is displayed within the ceramic substrate area, there is a drawback that it becomes impossible to identify the history when a plurality of sheets are stacked.

It is an object of the present invention, in order to eliminate the above-mentioned drawbacks found in the conventional products, to make it possible to easily read the indication of the provenance of each sheet of a multilayer ceramic substrate made by stacking a plurality of ceramic sheets even after lamination. The object of the present invention is to provide a multilayer ceramic substrate that makes it possible.

[Means for solving problems]

In the present invention, the history identification display of each ceramic sheet constituting the multilayer ceramic substrate is provided in contact with the outline cutting line of the multilayer ceramic substrate.

[Effect]

Since the identification mark is placed on the external cutting line,
In the state where the outer shape is cut after lamination, the history identification marks of all the ceramic sheets will appear on the side surface of the multilayer ceramic substrate.

〔Example〕

An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view showing the overall structure of a multilayer ceramic substrate. The multilayer ceramic substrate is composed of a plurality of ceramic sheets 1, and a through hole history identification display 4 and a wiring pattern history identification display 5 of each ceramic sheet 1 are shown on the side surface. FIG. 2 shows a plan view of the ceramic sheet 1. The identification display position mark 3 indicates, for example, a history number, and the display position is determined in advance on each ceramic sheet 1 in common and is formed with a printed pattern. . A through hole history identification display 4 indicating the history of the through hole and a wiring pattern history identification display 5 indicating the history of the wiring pattern are provided at predetermined positions of the identification display position mark 3 in contact with the outline cutting line 2. Here, when ceramic sheets are stacked, even if an identification display position mark is provided on the intermediate layer ceramic sheet of a multilayer ceramic substrate, the identification display position mark on the intermediate layer ceramic sheet will not actually be visible. The display position mark may be provided at least on the outer ceramic sheet, and thereby the positional relationship between the identification display position mark and the history identification display can be clearly recognized.

FIG. 3 is a sectional view showing the process of forming a multilayer ceramic substrate. First, a through hole 6 is drilled in each ceramic sheet 1, and at the same time, a through hole for a through hole history identification display 4 is placed in contact with the through hole so as to straddle the outline cutting line 2, and an identification display position mark shown in FIG. 2 is made. Drill a hole corresponding to step 3. Next, the through hole 6 is filled with a conductive paste such as tungsten (W) for forming the through hole, and the through hole for the through hole history identification display 4 is also filled in the same manner. Next, the wiring pattern 7 is printed, and the wiring pattern history identification display 5
The ceramic sheet 1 is formed by printing the marks so as to straddle the outline cutting line 2 and corresponding to the identification display position mark 3 shown in FIG. Next, after laminating each ceramic sheet 1, the through-hole history identification display 4 and the wiring pattern history identification display 5 of each ceramic sheet 1 appear on the side surface by cutting along the outline cutting line 2.

When the through hole 6 and the wiring pattern 7 have different histories, as in the above embodiment, by displaying their respective histories as the through hole filled with conductive paste for the former and the wiring pattern for the latter, it is possible to distinguish between the two. It can be easily detected that there is a combination of appropriate provenance. If both are the same, either one may be used to identify the history.

In addition, in the above embodiment, through holes are drilled only in necessary locations and all of them are filled with conductive paste, but in advance, through holes are standardized and through holes are drilled at all grid positions, and further identification is required. All the through-holes for display may be opened in the same manner, and only the necessary through-holes may be filled with conductive paste. In this case, the filling of paste for display is also carried out selectively so as to represent the provenance.

〔Effect of the invention〕

As described above, according to the present invention, the history of each sheet of a multilayer ceramic substrate can be easily identified, and appropriate quality control can be achieved.

[Brief explanation of drawings]

Fig. 1 is a perspective view for explaining the overall configuration of an embodiment of the present invention, Fig. 2 is a plan view of a ceramic sheet showing an embodiment of the invention, and Fig. 3 is a diagram of an embodiment of the invention. FIG. 3 is a cross-sectional view showing the process of manufacturing a multilayer ceramic substrate. 1...Ceramic sheet, 2...Outline cutting line,
3...Identification display position mark, 4...Through hole history identification display, 5...Wiring pattern history identification display, 6
...Through hole, 7...Wiring pattern.

Claims (1)

[Claims] 1. In a multilayer ceramic substrate formed by stacking a plurality of ceramic sheets provided with through holes and conductor wiring patterns, at least an outer ceramic sheet of the plurality of ceramic sheets is provided with an identification display position mark, and each of the ceramic sheets is provided with an identification display position mark. For each sheet, a history identification mark of the through hole and conductor wiring pattern in the sheet is provided in a position that is in contact with the outline cutting line of the multilayer ceramic substrate and corresponds to the identification mark position mark when stacked, and these ceramic sheets are stacked. A multilayer ceramic substrate characterized in that, in a state in which the ceramic sheet is further cut into an outline, a history identification mark of the ceramic sheet appears at a position corresponding to the identification mark on a side surface of the multilayer ceramic substrate.