JPS59181690A - Method of positioning screen printing time - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (a1 Technical Field of the Invention Ceramic wiring boards are manufactured by printing conductor paste and insulator paste on a ceramic substrate by screen printing and firing them. When printing the paste, each conductor pattern and The insulator patterns must be printed in proper registration with each other, and the present invention relates to a method for such registration during double-line printing.

Background of TBL technology Ceramic base 15. In thick wiring boards created by printing conductive paste and insulating paste on a substrate and baking them, the patterns of each layer must be aligned correctly in order to increase the wiring density.

For this reason, alignment marks are required to have clear contours and facilitate alignment.

FIG. 1 is a sectional view showing the screen printing method. A substrate 3 is set on a suction disk 2 provided above a suction chamber 1,
The paste is printed on the substrate 3 by pressing and moving the squeegee 5 from above the screen 4 provided on the substrate 3. At the same time, a vacuum pump is used to perform vacuum suction, and the substrate 3 is suctioned and held by the suction plate 2 in the direction shown by the arrow.

FIG. 2 is a cross-sectional view of a ceramic wiring board produced by printing and firing a pattern using a screen printing method. First, a conductor pattern C1 is created on the ceramic substrate 3 by printing and firing a conductor paste. And in the area where there is no conductor pattern C1,! i! ! The insulator pattern 1z is created by printing and baking the edge paste. Next, create a via C to connect the conductor patterns on the inner layer and the upper layer by printing and baking conductive paste, and
An insulator pattern I4 is created by printing and baking an insulator paste on the area where there is no 3. And to form the outer layer,
A conductor pattern C5 is provided by printing and firing a conductor paste,
An insulator pattern Ic is provided in an area where there is no conductor pattern C5 by printing and baking an insulator paste. Finally, solder C7 is provided on the conductor pattern C5, and the terminals 7 of the mounted component 6 are soldered.

By repeating the printing and firing of the paste in this way, conductor patterns and insulator patterns are created one after another. Therefore, patterns C1 and 12, C3 and 14, and Cs and IL on the same plane must be aligned accurately, and if the upper and lower patterns are not aligned accurately, the contact between the eyebrows due to the via [design I can't do it properly.

tc+Prior Art and Its Problems Conventionally, alignment marks as shown in FIG. 3 have been used to perform such alignment. In this figure (
A) is a longitudinal cross-sectional view, and (b) is a plan view. CI, C3
, cs are marks made of conductors, and each conductor pattern C+, C:I in FIG.

When printing C5, it is printed on the same screen at the same time. In addition, j2, l(, IC are marks made of an insulator, and are printed on the same screen at the same time when printing each insulator pattern I″2,]+, It in FIG. 2.The alignment mark is , printed on the corner of the substrate 3.

The marks C+ % C) and Cs made of conductors each have a cross shape as shown in Figure (B). The marks 12.11 and j& made of an insulator are formed by printing chemical compound paste in areas where the cross marks CI, C3, and C5 are not present, respectively. That is, as shown in FIG. 4(a), the conductive pattern C1 and the cross mark c1 in FIG. 2 are printed on the same screen. Next, when printing the insulator pattern 12, (b)
A mark i made of an insulator is placed in an area where there is no cross mark c1, as shown in FIG.

, but first, check the misalignment of the alignment mark part during preliminary printing (test printing) and correct the position. If the cross mark c1 and negative mark 12 match, then the conductor pattern C1 and insulator pattern I2 can be printed. This means that it is aligned with the screen. Then, the insulator pattern 11 is printed.

When printing the conductor pattern C1, a cross mark C3 like (c) formed by the same screen is printed. At this time as well, provisional printing is performed in the same manner as when printing the insulator pattern I2, and the position is corrected by aligning with the conductor mark C1 or the negative mark 12, and then the conductor pattern C3 is printed. Thereafter, in the same manner, a mark 14 made of an insulator is printed in an area where there is no cross mark C3, and after alignment, an insulator pattern I4 is printed.

In this method of printing and aligning marks each time the printing pattern is changed, insulator marks iz
If the cross-shaped conductor marks CI % G3, cs fit perfectly in the cross-shaped areas of , is , ia, then the patterns of each layer shown in Fig. 2 will be accurately aligned. , it is extremely difficult to fit the actual 1iX perfectly.

That is, it is extremely difficult to precisely align the positive cross mark C1 and the negative mark 12, which is an inverted cross shape, and as a result, a gap is created at the boundary 8.
On the contrary, there are parts where they are correct to each other. This phenomenon is caused by the cross mark CJsCS and the negative mark i4, iv
The same problem occurs when printing. Also, the lower ff1(c
If such a misalignment occurs between + and 1), the next layer is not aligned, and as the marks are printed as shown in Figure 5, the marks become blurry and difficult to distinguish. E-misalignment is likely to occur, and the amount of deviation becomes large. As a result, each pattern CI, 12sC in Fig. 2:
As 1, I-, . . . are printed, a shift occurs between each pattern, and the shift becomes larger.

Therefore, it is difficult to create fine patterns with high wiring density using thick film technology.

Td) Purpose of the Invention The purpose of the present invention is to eliminate such problems in the conventional alignment method during screen printing and to enable accurate alignment by improving alignment marks. .

(e1 Structure of the Invention In order to achieve this object, the present invention aligns a mark made of a conductor printed with a screen for printing a conductor pattern and a mark made of an insulator printed with a screen used to print an insulator pattern. By using this method, in the screen printing method for printed circuit boards that aligns each pattern, a mark with a pattern in the right angle direction is printed only once as a reference mark, and from then on, each pattern of this reference mark and the tip Opposing marks having opposing J-oriented patterns are printed in sequence each time the printing pattern is changed, and the opposing marks are printed each time the printing pattern is changed.
A method is adopted in which the distance between the reference mark and C is gradually increased (and alignment is performed so that the perpendicular pattern serving as the reference and each pattern facing it are arranged in a row of 11).

(Example of f1 invention) Next, how the alignment method during screen printing according to the present invention is actually implemented will be explained using an example.

FIG. 6 shows the first shape of the mark used in the method of the present invention.
Figures 7(A) to 7(E) showing the embodiment are diagrams showing the alignment process using these marks, with the upper row showing a plan view and the lower row showing a longitudinal direction. The cross square C1 formed of a conductor has the same shape as the conventional one. However, unlike in the past, the cross mark is not printed only for the first time, and the mark from the second and subsequent printings of the conductor pattern is
Instead of a cross mark, a mark with the same shape as the insulator pattern is used. That is, the cross mark (mark '2, C'3, tL % C'S,' of the other side aligned with 1)
& has a shape having patterns 91 to 94 in which each side and tip of a cross face each other. Also, the pattern width of each side 101...104 of the cross mark and the pattern 91
. . .94 is equal to the pattern width, so the edges on both sides of patterns 101 and 91 are aligned in a straight line, and the edges on both sides of other patterns 102...104 and 92...94 are aligned in a straight line, respectively. If they are aligned, it means that the cross mark c1 and the direction marks C, c', 'l, C'S, and C[ are accurately aligned.

By the way, the cross mark cI is printed only the first time, and when printing the conductor pattern for the second and third time, the cross marks C'3 and C''5, which have the same shape as when printing the insulator mark, are used in exactly the same way. Therefore, unlike the conventional method, the opposing marks are printed with insulator marks and conductor marks alternately arranged one above the other.

Also, facing marks t2, C'2, C4, C'5゛ (L is as the number of layers increases due to changes in the printing pattern,
The opposing distance from the reference cross mark CI gradually increases. That is, between the opposing mark patterns 91 and 93, 92 and 94
The upper facing mark is formed so that the distance between the marks is larger than that of the upper facing mark.

Next, a method of aligning multilayer patterns using marks having such a shape will be explained with reference to the process diagram shown in FIG. First, as shown in (a), the cross mark C serves as a reference.
1, and after printing the conductor pattern C1, print an opposing mark (l) made of an insulator as shown in (b) and align it. In this case, as described above, each side of the cross mark
Pattern 91 of 01...104 and opposing mark t2...
・Align so that the patterns 94 face each other and both edges of the patterns facing each other are aligned in a straight line. Note that this alignment is performed by repeatedly moving the screen 4 relative to the substrate 3 and performing trial printing. If the trial printing results in accurate alignment, fix the mutual positions and insulator pattern 1,
print.

When printing the twice-opened conductor pattern C3 on σζ, the cross mark is not printed, but an opposing mark C'3 is printed with the conductor pattern as shown in (c). In this case, since the upper opposing mark C'' is larger than the lower opposing mark 12, the opposing mark C'3 is aligned so that both edges of the opposing mark 12 and C'J are aligned in a straight line. Alternatively, the opposing mark C'3 and the cross mark C1 may be aligned so that both edges of the patterns are aligned with each other.

Next, when printing the insulator pattern I4, in the same way as when printing the conductor pattern C3, a facing mark ζ4 is printed, and both side edges are aligned with the pattern of the lower facing mark C'3 or cross mark c1. Align to.

Similarly, as shown in (E), the lower facing mark (
On top of 4, print opposing marks as C'5, '6...
Align. After printing one cross mark CI that serves as a reference in this way, when printing conductor patterns and insulator patterns, print with the opposing mark right, and in this case, print with the reference mark or print first. Perform alignment-U with the opposite mark that has been set.

The opposing mark is a one-way mark on the lower side; the opposing mark in the above example is enlarged so that the edges of the opposing marks do not overlap. Therefore, unlike in the past, there is no problem where the edges of the marks do not fit together perfectly, causing the marks to gradually become blurry.

Although the explanation was given using a cross mark as an example of a reference mark,
As long as the mark has a positioning pattern in both the direction and the Y direction, an L-shaped pattern CI as shown in FIG. 8 may be used, for example. In this case horizontal/directional pattern 101
Alignment in the Y direction is performed using the horizontal pattern 91 of the opposing mark (2), and alignment in the X direction is performed using the vertical pattern 102 and the vertical pattern 92 of the opposing mark. A pattern 101.102 forming a pattern 101.102 and a pattern 101.1 in a direction perpendicular to the pattern 101.102
02 and opposing marks having sides 91 and 92 whose tips face each other can be used for positioning according to the method of the present invention.

Further, in the illustrated example, the cross mark is formed of a conductive pattern, but conversely, the cross mark may be formed of an insulating pattern, and the opposing mark may be formed of a conductive pattern. However, in terms of mark identification, it is preferable that the reference mark has a different color from the base 1 and the length 3.

The substrate is not limited to a ceramic substrate, but can also be used as a resin printed circuit board if a low-temperature paste is used.

(g1 Effects of the invention As described above, according to the present invention, a perpendicular pattern having at least two perpendicular patterns, such as a cross mark, is used as a reference mark, and the tips thereof are opposed to the perpendicular pattern. An opposing mark having a pattern is printed.At this time, the opposing pattern facing the pattern in the perpendicular direction is bonded with the pattern of the reference mark by 1'+% for each time the number of opposing layers decreases. It's about to get bigger.

Therefore, unlike the conventional method of printing a pattern that fits perfectly into the blank space using the relationship between negative and positive, as you print multiple layers of marks, the pattern does not shift and the edges become blurry. do not have. In addition, the base:f=~ mark is printed only once, and then the alignment marks are printed based on this reference mark. The mark will not be blurred. Moreover, when parts are automatically mounted after completing printing 1 firing, by probing this reference mark with a check bin, it can also be used for positioning during part mounting. pattern 1
If the marks are formed in a circular pattern, the marks will not be misaligned, so positioning during component mounting can be performed extremely accurately.

[Brief Description of the Drawings] Figure 1 is a sectional view of a screen printing device, Figure 2 is a sectional view of a multilayer ceramic wiring board, Figure 3 is a sectional view and plan view of a conventional alignment mark, and Figure 4 is a sectional view of a conventional alignment mark. Figure 5 is a cross-sectional view of the alignment mark printed by the conventional alignment method, and Figure 6 is the alignment method used in the alignment method of the present invention. FIG. 7 is a plan view of the mark, FIG. 7 is a diagram showing the alignment method according to the present invention in the order of steps, and FIG. 8 is a plan view showing another embodiment of the alignment mark. In the figure, 3 is a ceramic substrate, 4 is a screen, and C+
, Cal, Cs are conductor patterns, I2,
6 is an insulator pattern, C1 is a cross mark, 101...
104 is each side of the cross mark, tx, c'ko, l can%C'
5, (L is the opposing mark, 91...94 is the opposing mark
- Indicate each side of ri.

Claims (1)

[Claims] By using a mark made of a conductor printed on a screen for printing a conductor pattern and a mark made of an insulator printed on a screen for printing an insulator pattern for alignment, the distance between each pattern can be adjusted. In a screen printing method for printed circuit boards that performs alignment, a mark with a pattern in the right angle direction is printed only once as a reference mark, and thereafter, each pattern of this reference mark has an opposing pattern that faces each other. Opposing marks are printed sequentially each time the printing pattern is changed, and each time the printing pattern is changed, the opposing mark is printed gradually with a larger opposing distance from the base rlls mark, and the perpendicular direction pattern that becomes the standard is printed. A method of alignment during screen printing, characterized by aligning this and each opposing pattern in one row Ii+ii.