JPH07105582B2 - Ceramic substrate inspection method - Google Patents

Description

Detailed Description of the Invention 【Overview】

Regarding a method of inspecting a ceramic substrate formed with through vias, it is possible to easily perform open check and short check of a fired ceramic substrate, which enables reduction of inspection man-hours and a highly reliable ceramic substrate. For the purpose of providing a method for inspecting a ceramic substrate that can obtain the above, a front surface and a back surface are printed so that the front and back of the through vias are alternately connected to a ceramic substrate that connects the front surface and the back surface with through vias. Two or more check patterns are provided, and the open check is performed by the continuity check of the check patterns of the same system, and the short check is performed by the continuity check between check patterns of different systems.

[Industrial applications]

The present invention relates to a method of inspecting a ceramic substrate having a through via. 2. Description of the Related Art In a large computer, a ceramic substrate made of ceramics and laminated in multiple layers is used to achieve high speed and high functionality. Through-vias are formed in the laminated ceramic substrates to establish conduction between the layers,
When the ceramic substrate is fired, the through vias may be opened without being connected between the layers, or the adjacent through vias may be short-circuited. Therefore, the inspection is required. However, due to the demand for higher density of the ceramic substrate, the pattern is miniaturized, short circuit and open check are troublesome, and the number of inspection steps is increasing. Under these circumstances, there is a demand for a method of inspecting a ceramic substrate that can easily perform an open check and a short check of a ceramic substrate having through vias and fired with a small number of steps.

[Prior art]

Conventionally, a method of inspecting a ceramic substrate is as shown in FIG. 4, in which a through via 20 is formed and fired.
A conductor film 30 is formed on the entire back surface 110 by sputtering or plating, and the ceramic substrate 10 is plated with the conductor film 30 as an electrode. Then, by checking the presence or absence of the plating layer 40 formed on the exposed portion 210 of the through via 20 on the surface 120 side where the conductor film 30 is not formed, the continuity of the through via 20 is checked, and then the front and back surfaces are polished. Then, the conductor film 30 and the plating layer 40 are removed.

[Problems to be Solved by the Invention]

However, according to such a conventional method of inspecting a ceramic substrate, it is possible to simultaneously check the continuity of a large number of through vias, but it is not possible to perform a short check between the through vias. That is, in a high-density ceramic substrate, when the through vias are close to each other, when the pattern of the land portion is crushed during stacking or when the short circuit occurs due to deformation during firing, the conventional method of checking only the continuity of the through vias However, it has a drawback that the defect of the ceramic substrate cannot be checked. The present invention has been made to solve the above-mentioned drawbacks, and it is possible to easily perform a short check as well as an open check of a fired ceramic substrate, reduce the number of inspection steps, and achieve high reliability. An object of the present invention is to provide a method for inspecting a ceramic substrate, which can obtain a ceramic substrate.

[Means for Solving the Problems]

The present invention will be described with reference to FIGS. 1 and 2 corresponding to the embodiment. The through vias 2, 2, ... Formed in the ceramic substrate 1 are formed on the front surface 11 and the rear surface 12 of the ceramic substrate 1. , Check pattern 3 is connected. The check pattern 3 is continuous by connecting the through vias 2, 2, ... Alternately on the front surface 11 side and the back surface 12 side 1
It is printed so that two or more system patterns are provided. An open check is performed by checking the continuity of the check patterns 3 of the same system, and a short check is performed by checking the continuity between the check patterns 3 and 3 of different systems.

[Action]

Based on the above method, in the present invention, by checking the continuity check of the check pattern 3 of the same system, the through vias 2, 2, ... Connected continuously by the check pattern 3 of the same system are formed in the ceramic substrate 1. You can check if it is formed correctly without opening. Further, by checking the continuity between the adjacent check patterns 3 and 3 of different systems, the through vias 2 and 2 adjacent to the check patterns 3 and 3 of the different system are short-circuited to each other. You can check whether it is in a state. Therefore, the open check and the short check can be performed by measuring the continuity of the check pattern 3, and unlike the conventional inspection method of only the open check, the ceramic substrate having a fine pattern can be also checked by the short check. A highly reliable inspection can be performed.

【Example】

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. As shown in FIGS. 1 and 2, the ceramic substrate 1
Is a substrate material 13 having a via portion 21 in which a conductive metal is filled by punching a green sheet on which a wiring pattern is printed.
Are laminated in multiple layers and fired to form the through via 2 by the via portion 21, and the exposed portion 22 of the through via 2 is formed on the front surface 11 and the back surface 12.
Check pattern 3 is printed to connect 22 ... As shown in FIG. 1, the check pattern 3 alternately connects the through vias 2, 2, ... Between the front surface 11 side and the back surface 12 side, and the connected through vias 2, 2 ,. It is formed to be continuous. And check pattern 3
Are provided on the ceramic substrate 1 in two or more systems.
As shown in the figure, so that the through vias 2a and 2b formed close to each other are not connected to the check patterns 3 of the same system, they are connected to the check patterns 3a and 3b of different independent systems, respectively. Enables short-circuit check of through vias 2a and 2b that are easy to short. Then, terminal pads 4 for conducting a continuity check are printed on both ends of each check pattern 3. Explaining the open check method of the ceramic substrate, the terminal pad 4 of the check pattern 3 of the same system,
Check continuity between four. That is, in the case of the check pattern 3a, the conduction between the terminal pads 4a on both ends is measured, and the through vias 2, 2 connected to the check pattern 3a are measured.
It can be checked whether ... is not open between the stacks of substrate material 13,13. Next, explaining the method of short check,
In order to check the continuity between the different check patterns 3a and 3b, the distance between the terminal pads 4a and 4b is measured. That is, when the through vias 2a and 2b respectively connected to the different check patterns 3a and 3b are short-circuited, the short check can be performed by measuring the conductive state between the different check patterns 3a and 3b. In the above embodiment, the check pattern 3 is set to 2
Although the description has been given with the example in which the through vias 2 are formed in the system, when three or more through vias 2 are arranged close to each other, the check pattern 3
The number of series of 3 is increased to 3 or more, each adjacent through via 2 is arranged in the check pattern 3 of another system, and the continuity between the check patterns 3 and 3 is checked. As shown in FIG. 3, the ceramic substrate 1 which had no abnormality by the open check and the short check,
By polishing the front surface 11 and the back surface 12, the check pattern 3 can be removed to obtain a finished product.

【The invention's effect】

As is clear from the above description, according to the ceramic substrate inspection method of the present invention, not only the open check but also the short check can be performed by checking the continuity of the check patterns printed on the front and back surfaces of the ceramic substrate. Since it is possible to easily and surely inspect a ceramic substrate that has a high density and is easily short-circuited during formation, it is possible to reduce the number of steps for the inspection and obtain a highly reliable ceramic substrate.

[Brief description of drawings]

1 is a plan view for explaining an embodiment of the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, FIG. 3 is a sectional view showing a completed ceramic substrate, and FIG. 4 is a conventional example. It is sectional drawing explaining. In the figure, 1 is a ceramic substrate, 11 is a front surface, 12 is a back surface, 2 is a through via, and 3 is a check pattern.

Claims (1)

[Claims] 1. A surface (11) by means of through vias (2, 2, ...).
Check by printing on the front surface (11) and the back surface (12) so that the through vias (2, 2, ...) are alternately connected to the ceramic substrate (1) that conducts between the surface and the back surface (12). The feature is that two or more patterns (3) are provided, the open check is performed by the continuity check of the check pattern (3) of the same system, and the short check is performed by the continuity check between the check patterns (3, 3) of different systems. Inspection method for ceramic substrates.