JPH0710587B2 - Printing mask tension abnormality detection method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a print mask tension abnormality detection method for detecting a tension abnormality of a print mask during manufacturing of a thick film circuit board.

[Conventional technology]

In the method of manufacturing a thick film circuit board, generally, a through hole or a dividing groove is first formed in an unfired ceramic sheet and then fired to obtain a ceramic board. Next, a conductive material paste is printed on one main surface of the ceramic substrate and the through holes by using a printing mask patterned into a predetermined shape, dried and then baked to form a conductive pattern. To do. In this way, the conductor pattern composed of the thick film coating of the first layer is formed. In the same manner as described above, the resistive material paste, the insulating material paste, etc. are respectively patterned into a predetermined shape using a printing mask. The thick film coatings of the second layer and the third layer are sequentially formed by printing. Then, a large number of divided thick film circuit boards can be obtained from one ceramic substrate by dividing by the dividing groove.

As a printing mask used in the thick film coating film forming step, a support such as a mesh having a masking portion formed thereon is adhered and fixed on a support frame made of a metal material or the like with an adhesive. The tension of the print mask thus prepared is measured before use. It is possible to use only for those whose measured value of this tension is within the predetermined standard range, even if the tension is stronger or weaker than this, when the squeegee rubs the print mask,
In the former case, the pattern of the printed coating film is liable to be faint, and in the latter case, the pattern of the printed coating film is apt to be distorted, drooped, bleeding or the like, and therefore is not used.

As described above, the tension of the print mask for forming the conductor pattern, the resistor pattern, the insulator pattern, etc. is checked, and only the print mask within the standard is set on the printing machine, and the conductive material paste and the resistance material are placed on the ceramic substrate. The paste, the insulating material paste, and the like are sequentially printed, but the tension of each print mask gradually decreases as the number of times of printing increases.

As described above, the tension is lowered and the non-standard one cannot be used. However, the life of the print mask from this point depends on various conditions such as the size and thickness of the mask and the print pattern. When a standard print mask is used, the number of prints is 5000 to 10000.

Therefore, conventionally, every time a predetermined number of times of printing is performed, the print mask is removed from the printing machine, the tension of the print mask is measured in the same manner as described above, and when the measured value of the tension deviates from the predetermined standard value, this is removed. It is being used and replaced with another new print mask.

[Problems to be Solved by the Invention]

However, in the above conventional method, each time the tension of the print mask is measured, the print mask is removed from the printing machine, the tension of the print mask is measured,
The work of reattaching this print mask or a new print mask to the printing machine is required, and the printing machine must be stopped during that time, and the alignment work when mounting the printing mask on the printing machine is also a great deal. It took a lot of time, and the work efficiency was bad.

An object of the present invention is to provide a tension abnormality detection method for a print mask capable of reading fluctuations in the tension of the print mask while the print mask is attached to a printing machine, thereby reducing the printing work efficiency of a circuit pattern. It is to prevent it.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the present invention has a dividing groove capable of dividing one substrate into a plurality of sections, and printing by using a print mask provided with a circuit pattern under tension in each section. After the formation, the thick film circuit board is divided into the respective sections to form the thick film circuit board. In the manufacturing process of the thick film circuit board, in addition to the circuit pattern, the image portion of the alignment mark is provided outside the circuit pattern on the print mask. When the printing is performed with this printing mask, the alignment marks are printed by printing in the vicinity of the contour lines or the dividing grooves at both ends in the printing direction of the substrate or each section, and the distance between this mark and the contour line of the substrate or Provided is a tension abnormality detection method for a print mask, which detects the tension abnormality of the print mask depending on whether or not the distance between the mark and the dividing line of each section varies. Is shall.

[Action]

Since the image part of the alignment mark is formed on the print mask and the alignment mark is printed on the outline of the substrate or in the vicinity of the division groove of each divided section of the substrate using this print mask, the outline of the substrate and this mark of the mark are printed. By measuring the distance or the distance between the dividing groove and this mark and checking for the fluctuation, it is possible to know the fluctuation of the tension of the print mask.

〔Example〕

Next, an embodiment of the present invention will be described with reference to FIGS.

Example 1 In FIG. 1, 1 is a ceramic substrate and 2 is a dividing groove. The dividing groove 2 forms a first dividing section 2a and a second dividing section 2b, and circuit patterns 3 and 3'are formed in each. The circuit pattern 3 has a conductor pattern 3a and a resistor pattern 3b, and the circuit pattern 3'is a conductor pattern 3 '.
a, resistor pattern 3'b. Although an insulator pattern is further formed, the illustration is omitted.

Further, 4a and 4b are alignment marks of the first divided section, which are at both ends in the printing direction of the first divided section and have no soldering lands 3a-1, 3a-1 ... Of the conductor pattern 3a. One of the two corners, i.e., both corners above the drawing, is simultaneously printed by using the same conductive material paste together with the conductor pattern formation. As shown in FIG. 2, the shape is a square with a side of 0.3 mm, and when printed using a printing mask with normal tension, the dividing grooves 2 and 2 are
Printed 0.2 mm apart. Reference numerals 4'a and 4'b are alignment marks of the second divided section, which are formed similarly to the alignment marks of the first divided section. 3'a-1, 3'a-1 ... Soldering lands.

In this way, the ceramic substrate 1 has a plurality of divided sections, each of which has the circuit patterns 3, 3 ', etc., and is divided by the dividing grooves 2 to form a thick film circuit board. As described in the above-mentioned conventional technique, the manufacturing process of the membrane circuit board is performed by firing an unfired ceramic sheet having through holes (not shown in FIG. 1) and dividing grooves to produce a ceramic substrate. Then, a conductive material paste, a resistance material paste, and an insulating material paste are sequentially printed on this using a print mask of each circuit pattern. This is continuously performed on many ceramic substrates.

At this time, the alignment mark is printed at the same time when the conductive material paste for the first layer is printed. As described above, when the conductive material paste of the first layer is sequentially printed on a large number of ceramic substrates and the alignment mark is printed at the same time, when the tension of the print mask is loosened, the distance between the mark and the dividing groove is changed. Therefore, the variation of this distance can be judged by visually observing this with a microscope, for example. This is also performed for the alignment marks for the second divided section and other divided sections, and it is determined whether or not the print mask is loose.

In this case, for example, the space between the conductor pattern wiring is 0.1 mm.
Then, the distance between the dividing groove and the alignment mark is 0.1 mm.
If they are misaligned, the wirings may overlap, so if the distance between the dividing groove and the alignment mark is within 0.2mm ± 0.1 in Fig. 2, loosening of the tension of the print mask is acceptable and continue to use it. If the print mask is not outside this range, the print mask may be replaced.

Embodiment 2 As shown in FIG. 3, the ceramic substrate 11 is formed with the dividing grooves 12 and the circuit patterns 13 and 13 'are formed in the respective dividing sections 12a and 12b. When the alignment mark as shown in FIG. 1 cannot be printed due to a small space, soldering lands 13a-1, 13a-1 ..., 13'a-1, 1 of the circuit pattern are formed at both ends of the ceramic substrate 1 in the printing direction.
Alignment mark on the corner opposite to the side with 3'a-1 ...
14 and 14 'are printed and formed at the same time when the conductor pattern is formed as in the first embodiment. By doing so, the alignment mark and the outline 11 of the ceramic substrate 11 are formed as in the first embodiment.
The looseness of the tension of the print mask can be determined by measuring the distance between a and 11b and determining whether the variation is within the standard.

〔The invention's effect〕

According to the present invention, a circuit pattern is formed on a substrate having a plurality of divided sections by using a print mask, and in a process of manufacturing a thick film circuit board formed by dividing each section, for example, a conductor pattern of the first layer. Since a registration mark was formed by printing on the contour line of the substrate or on the side of the dividing groove when printing, the fluctuation of the distance between the contour line of the mark and the dividing groove was detected and judged to determine the tension of the print mask. You can know the changes. As a result, it is possible to know the change in the tension of the print mask while the print mask is attached to the printing machine, and to know the replacement time, so that the circuit pattern printing work can be performed without interrupting it unnecessarily. The efficiency can be increased.

[Brief description of drawings]

FIG. 1 is a plan view showing a part of a structure in which a circuit pattern is formed on a ceramic substrate used in one embodiment of the method of the present invention, FIG. 2 is a partially enlarged view thereof, and FIG. 3 is another embodiment. 2 is a plan view corresponding to that of FIG. 1 used in FIG. In the figure, 1 and 11 are ceramic substrates, 2 and 12 are dividing grooves, and 11
a, 11b are outlines, 2a, 2b, 12a, 12b are division sections, 3,
3 ', 13, 13' are circuit patterns, 3a, 3'a, 13a, 1
3'a is a conductor pattern, 3a-1, 3'a-1, 13a-1, 13'a-1
Is a soldering land.

Claims (1)

[Claims] 1. A substrate is provided with a dividing groove capable of dividing into a plurality of sections, and a circuit pattern is formed in each section by printing using a print mask to which tension is applied, and then divided into each section. In the manufacturing process of the thick film circuit board to form the thick film circuit board, the image portion of the alignment mark is formed outside the circuit pattern on the print mask in addition to the circuit pattern, and printing by the print mask is performed. In this case, the alignment mark is formed by printing in the vicinity of the outline or the dividing groove at both ends of the substrate or each section in the printing direction,
A method for detecting a tension abnormality of a print mask, which comprises detecting the tension abnormality of the print mask depending on whether or not the distance between the mark and the outline of the substrate or the distance between the mark and the dividing line of each section changes.