JPH071819B2 - Printed wiring board - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed wiring board used for mounting electronic components in various electronic devices and the like, and particularly to the printed wiring board. The present invention relates to a printed wiring board which is devised so that the positional relationship between the above pattern and the outline of the board can be easily inspected and selected.

(Prior art) Due to the automation of component mounting on printed wiring boards and the miniaturization of the final products that use printed wiring boards, the tolerance range for the position of each component in the product has become smaller. More than ever, there is a demand for improving the relative positional accuracy of a pattern on a printed wiring board and its outline. Although the manufacturing method of the printed wiring board has been improved in order to meet this demand, there is a high possibility that products that are mass-produced in particular will include those that deviate from the relative range of the relative position.

Conventionally, as a method of increasing the efficiency of the inspection / selection on a printed wiring board, external observation inspection / selection by an alignment mark as shown in Japanese Utility Model Publication No. 56-108277 has been performed. That is, a positioning pattern consisting of a circular ring is provided on the front surface or the back surface of the printed wiring board, the circular processing that should be inscribed in the ring is performed at the same time as other processing, and then the positioning pattern and the By observing the positional relationship with the processed circle, the positional accuracy of the processing with respect to the pattern was judged.

However, in the above-mentioned method, first, the printed wiring boards must be observed one by one in order to perform the inspection and selection, and it is desired to improve the efficiency of reducing the inspection cost particularly for mass-produced products. Further, the positional relationship between the position of the circle machined in the alignment pattern and the other processed portion is not always constant. For example, the pattern positional relationship from the outline is added to the positional deviation between the patterns. The positions of the parts to be machined are misaligned. In particular, this value including a large positional deviation between the processed parts due to wear of the processing machine, which is likely to occur during mass production, indicates that the pattern position from the outline cannot be confirmed by the above method.

(Problems to be Solved by the Invention) The present invention has been made in view of the above circumstances, and a problem to be solved is to select a positional deviation between a pattern formed on a printed wiring board and an outline. Inefficiency and inaccuracy.

It is an object of the present invention to provide a printed wiring board that is both efficient and accurate in selecting the positional deviation.

(Means for Solving Problems) Means adopted by the present invention for solving the above problems will be described with reference to FIGS. 1 to 3 corresponding to the embodiment. ) Conductor circuit pattern (1
2) A printed wiring board characterized in that the alignment mark (13) formed at the same time is a triangular pattern having its base on the outline (14) of the substrate (11). As shown in FIG. 3, the substrate (11) is overlaid and the end face position of the alignment mark is externally observed by using a jig showing a good range in advance from the side surface as shown in FIG. This is done by doing.

(Operation of the Invention) The present invention has the following operations by adopting the above means.

First, according to the external observation shown in FIG. 3, the non-defective product has its triangular end surface appearing within a predetermined position range. Further, the triangular end surface of the defective product appears smaller or larger than a predetermined size (length), or appears displaced from a predetermined position. By making the mark triangular, the amount of change in size of the triangular end surface when the outer shape is misaligned is expanded and expressed compared to the amount of misalignment. Conventionally, it is possible to perform inspection more efficiently and more accurately than the inspection method in which the substrates are observed one by one and the slight processing deviation is observed and judged by the actual size.

(Example) Example 1 A printed wiring board was manufactured in which an alignment mark having one side of an equilateral triangle formed on the outline of the printed wiring board was formed simultaneously with the pattern formation of the printed wiring board.

When the positional deviation of the outer shape with respect to the pattern was selected, the inspection speed was 5 times that of the method using the conventional technique. In addition, the amount of inspection and selection errors was reduced by half.

Example 2 The same inspection as in Example 1 was performed in the step before the pin connection of the plastic pin grid array substrate which is a semiconductor mounting substrate. However, the provided alignment marks were obtuse isosceles triangles having a base on the outline and an apex angle of 120 degrees. With this product, the inspection speed is 10 times and the error rate is 5
It became one-third.

Example 3 By using a jig showing the allowable range for the positional deviation amount in the inspection of Example 2 on the side surfaces of the superposed substrates,
The inspection speed was 20 times, and the error rate was 1/50.

(Effects of the Invention) As described in detail above, according to the present invention, as illustrated in each of the above-described embodiments, the product is obtained by observing the position of the alignment mark seen on the outer end surface of the printed wiring board. Is defective, the end face of the alignment mark is out of a predetermined range or has a different size, so that inspection and selection can be performed easily and in large quantities. Further, by making the alignment mark triangular, it is possible to clearly know the size of the deviation.

[Brief description of drawings]

FIG. 1 is a perspective view showing a printed wiring board of the present invention.
Similarly, FIG. 2 is a plan view seen from above. FIG. 3 is a method diagram for inspecting and selecting the printed wiring board of the present invention. FIG. 4 is a partial plan view seen from the upper surface of a printed wiring board showing a conventional technique. FIG. 5 is a method diagram of an example of inspecting the printed wiring board of the present invention using a jig. DESCRIPTION OF SYMBOLS 11 ... Board, 12 ... Conductor circuit pattern, 13 ... Alignment mark of the present invention, 14 ... Board outline, 15 ... Prior art alignment ring, 16 ... Machining hole, 17 ... … Jig, 18…
… Tolerance for misalignment.

Claims (1)

[Claims] 1. A printed wiring board having an alignment mark for inspecting and selecting a positional relationship between a conductor circuit pattern formed on a substrate and an outline of the substrate, wherein the alignment mark is the conductor. A printed wiring board, which is formed at the same time as a circuit pattern and has a triangular shape whose base is on the outline of the substrate.