JPH10135699A - Device and method for detecting positional deviation of circuit board at inspecting time - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely electrically detect the positional deviation including directional duration of an objective circuit board with respect to the inspection machine. SOLUTION: Positional deviation detecting patterns 11 having prescribed areas are formed in a state where the patterns 11 are painted all over in the blank spaces of an objective circuit board 10 and, at the same time, pin groups, each of which is composed of one center check pin 12e which is brought into contact with the central part of each pattern 11 and a plurality of peripheral check pins 12a-12d which are respectively brought into contact with difference points on the periphery of each pattern 11, are provided correspondingly to the patterns 11 on a circuit board inspection machine side. The positional deviation of the circuit board 10 with respect to the inspection machine is detected from the continuity and noncontinuity between the center pin 12e and each peripheral pin 12a-12d.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device and a method for detecting a positional deviation in inspecting a circuit substrate. More specifically, the present invention relates to a method for inspecting the quality of a circuit substrate on which wiring patterns are formed at a high density. The present invention relates to a technique capable of accurately detecting a positional shift of a circuit board to be inspected with respect to a circuit board inspecting machine, including a direction of the shift.

[0002]

2. Description of the Related Art In a pin board type board inspection apparatus, for example, probe pins (conductive contact pins) corresponding to a point to be measured on a board to be inspected are placed on an acrylic plate of an inspection jig.
Are used, and the respective probe pins are simultaneously brought into contact with the printed circuit board to be inspected.

As described above, in the pin board system, the point to be measured and the probe pin have a 1: 1 relationship. However, since the probe pin is held by a sleeve having a predetermined diameter, the interval between the pins is reduced. But there is a limit. Therefore, a single pin board cannot cope with a high-density mounting board in which measured points are extremely close.

In view of the above, a circuit board inspection machine has been developed in which fine conductive projections are brought into contact with a point to be measured via pressure-sensitive conductive rubber instead of the probe pins. FIG. The figure is shown. That is, the circuit board inspection apparatus 1 is configured to perform inspection of a wiring pattern formed on, for example, the front side of the circuit board 2 to be inspected.
And a lower jig plate 4 for inspecting a wiring pattern formed, for example, on the back surface side of the circuit board 2 to be inspected. For each of the jig plates 3 and 4, a double-sided wiring board or a multilayer wiring board made of, for example, a ceramic substrate or a synthetic resin substrate such as a glass epoxy resin is used.

Although not shown, a conductor circuit is formed on each of the jig plates 3 and 4, and a surface (front surface) facing the circuit board 2 to be inspected has a position corresponding to the point to be measured. In addition, a conductive contact terminal formed of fine conductive protrusions is formed. The conductive projections are much smaller than the probe pins, and the pitch between them can be made narrower. This makes it possible to support a high-density mounting substrate. An insulating resist film is formed on the surfaces of the jig plates 3 and 4 except for the conductive protrusions, so that the jig plates 3 and 4 are not electrically connected to the printed circuit board 2 by mistake.

[0006] Pressure-sensitive conductive rubber plates 51, 52 are respectively attached to the projection forming surfaces of the jig plates 3, 4 via, for example, a double-sided adhesive tape. Pressure-sensitive conductive rubber plates 51, 52
Is made of a rubber plate mixed with a predetermined metal powder, and is known to be non-conductive in a no-pressure state and to have a conductive part in a pressurized state.

The upper jig plate 3 has a vertically movable holding frame 6.
The lower jig plate 4 is set on the base plate A. In the inspection, the lower jig plate 4 and the printed circuit board 2 to be inspected are set on the base plate A using the positioning pins 7, 7 erected on the base plate A as a guide, and the holding frame 6 is lowered. The upper jig plate 3 is pressed against the printed circuit board 2 to be inspected.

As a result, the projections of the jig plates 3 and 4 and the corresponding points to be measured of the circuit board 2 to be inspected are electrically connected to each other via the pressure-sensitive conductive rubber plates 51 and 52, and a predetermined inspection is performed. A circuit check is performed according to the program. Although not shown, each of the conductive protrusions is formed of, for example, a metal film thicker than a resist film by applying nickel plating as a base on copper foil and applying gold plating thereon. A contact is formed, and the conductive contact is connected to a not-illustrated lead wire or the like from the back side of each jig plate 3, 4 through a not-shown conductor circuit formed on each jig plate 3, 4. Connected to the measuring instrument body via

[0009]

The circuit board inspection machine 1
According to the method described above, the conductive contact terminals are formed of fine projections much smaller than the probe pins, so that they can correspond to the measured points extremely close to each other on the high-density mounting board. Therefore, high accuracy is required for positioning when setting the circuit substrate 2 to be inspected in the substrate inspection apparatus 1.

However, when viewed from the product board level, the circuit boards 2 to be inspected are not necessarily of the same size, and each has a dimensional error caused by, for example, a cutting process. Therefore, although the positioning pins 7 are provided on the board mounting portion of the circuit board inspection machine 1, it is difficult to ask for a guarantee that the accurate positioning is performed.

Therefore, a non-defective substrate which has been previously confirmed as a non-defective product is prepared, and the non-defective substrate is aligned by trial and error until an initial inspection result (non-defective data) is obtained. Is to check the alignment condition visually. Further, since each circuit board has a dimensional error, the alignment state is visually checked every time. Therefore, considerable effort and time are required, and improvement in this regard has been desired.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to provide a method of detecting a position shift of a circuit board to be inspected with respect to a substrate mounting portion of a circuit board inspecting machine, including a direction of the shift. It is an object of the present invention to provide a circuit board position shift detecting device and a position shift detecting method which can be reliably detected electrically.

[0013]

In order to achieve the above object, a position shift detecting apparatus according to the present invention has a circuit board to be inspected disposed on a substrate mounting portion of a circuit board inspecting machine, and the circuit board to be inspected has When inspecting pass / fail, in a displacement detection device for detecting the presence / absence of displacement of the circuit board to be inspected with respect to the board mounting portion, the circuit board to be inspected is formed in a solid color with a predetermined area on the side of the circuit board to be inspected. One central check pin arranged to contact substantially the center of the misregistration detection pattern, a plurality of peripheral check pins arranged to respectively contact different peripheral portions of the misalignment detection pattern; A switch circuit for connecting one of the peripheral check pins to the central check pin while switching the peripheral check pins in a predetermined order; and controlling switching of the switch circuit. Continuity between said peripheral check pin and the central check pin during the switching, is characterized by comprising a control unit for detecting the presence or absence of the displacement of the circuit board to be inspected by a non-conductive.

In this case, the number of the peripheral check pins is three or more, and it is preferable in terms of detection accuracy that the peripheral check pins are arranged at equal angular intervals around the central check pin.

Further, in the method of detecting a displacement according to the present invention, a circuit board on which a predetermined wiring pattern is formed (a circuit board to be inspected) is placed on a substrate mounting portion of a circuit board inspecting machine, and its quality is inspected. In doing so, a misregistration detection pattern having a predetermined area is formed in a blank area on a blank portion of the circuit board to be inspected, and the circuit board to be inspected is provided on the circuit board inspecting machine side. When being placed at an appropriate position, one central check pin that contacts substantially the center of the misregistration detection pattern and a plurality of peripheral check pins that respectively contact different portions of the periphery of the misregistration detection pattern are provided. Detecting the presence / absence of a displacement of the circuit board to be inspected by conduction / non-conduction between the center check pin and the plurality of peripheral check pins. It is characterized.

The position shift detection pattern may be circular or polygonal as long as it is a solid pattern having a predetermined area. However, when detecting shifts in the X-axis direction and the Y-axis direction, each of the axes is detected. It can be said that a square shape having a side along is simplest and preferable.

As described above, if the misregistration detection pattern is, for example, a solid square, the center check pin is located substantially at the center and the peripheral check pins are located at, for example, each peripheral edge of the detection pattern. Become. Therefore, it is possible to inspect the presence or absence of a position shift due to conduction and non-conduction between the center check pin and each peripheral check pin. That is, there is no displacement when the central check pin and all the peripheral check pins are electrically connected to each other, whereas when there is a non-conductive peripheral check pin between the central check pin and the central check pin, the direction is the same. Is determined to be misaligned.

[0018] At least one pair of the displacement detection patterns is arranged along a diagonal line of the circuit board to be inspected, and a center check pin and a peripheral check pin are provided on the circuit board inspection machine side for each displacement detection pattern. It is preferable to assign the following, whereby it is possible to detect the presence / absence of a positional shift including a shift in the rotation direction of the circuit board to be inspected.

When arranging at least one pair of the positional deviation detection patterns along a diagonal line of the circuit board to be inspected, if the positional deviation detection pattern is an odd-numbered polygon, each of the positional deviation detection patterns is set to 180 degrees. It is preferable from the viewpoint of detection accuracy to adopt a rotationally symmetric arrangement.

Each of the above check pins may be a probe pin used in an ordinary circuit board inspection machine. However, in order to correspond to a high-density mounting board, it is necessary to use a jig plate surface of the board inspection apparatus. It is preferable that the formed fine protrusions have conductivity.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment will be described with reference to FIGS. 1 to 9 in order to better understand the technical concept of the present invention. In this embodiment, the circuit board inspection machine itself is not shown, but the pin board type board inspection machine described above or the fine projection shown in FIG. Any of the circuit board inspection machines of the type that makes contact with the measurement points described above.

FIG. 1 shows a printed circuit board 10 as a circuit board to be inspected. Although not shown,
A predetermined wiring pattern is formed in a pattern forming area of the printed board 10.

A misregistration detection pattern 11 as shown in an enlarged view in FIG. 2 is formed in a blank portion (a discarded plate portion) of the printed circuit board 10 other than the pattern forming area. In this embodiment, as shown in FIG. 1, two misalignment detection patterns 11 are provided on each of the opposed corners of the printed circuit board 10 along the diagonal line. Although both patterns have the same shape, if it is necessary to describe them separately, for convenience, one of them is 11a and the other is 1a.
1b.

In this embodiment, the misregistration detection pattern 11 is formed by a solid pattern of a square conductive film, and one side of the pattern is a regular square of, for example, 2 mm or more. Note that this displacement detection pattern 11 is preferably formed together with a wiring pattern (not shown). However, if the wiring pattern has a pattern of the same shape, it may be substituted.

On the circuit board inspection machine side, check pins (conductive contact terminals) are provided corresponding to the position shift detection patterns 11. The check pin may be either a fine projection or a probe pin contacted via a pressure-sensitive conductive rubber. Although not shown in this embodiment, the position of the check pin is indicated by a black circle in FIG. In the following description, these are denoted by reference numerals and used as check pins.

According to this, five check pins 12a to 12e are prepared for one position shift detection pattern 11. Of these, the check pins 12a to 12d
Printed circuit board 10
In the case where there is no displacement, the peripheral check pins whose installation positions are fixed so as to come into contact with substantially the center of each side of the detection pattern 11. One remaining check pin 12
“e” is a center check pin whose installation position is fixed so as to contact substantially the center of the displacement detection pattern 11.

The center check pin 12e and each of the peripheral check pins 12a to 12d are connected to the circuit board inspection machine side as shown in FIG.
Can be connected to each other via a switch as exemplified in FIG. According to this, the center check pin 1
2e and each of the peripheral check pins 12a to 12d,
On / off switches SW1 to SW4 are interposed respectively.

FIG. 4 exemplifies a schematic block diagram of the position shift detecting device. That is, the position shift detecting device includes a switch circuit 21 including the switches SW1 to SW4 for appropriately connecting the peripheral check pins 12a to 12d to the center check pin 12e, and switches SW1 to SW4 of the switch circuit 21. Switching is performed in a predetermined order, and each time switching is performed, the presence / absence of a position shift and the direction of the shift are detected based on the conduction / non-conduction state between the peripheral check pin (one of 12a to 12d) and the center check pin 12e. A CPU (Central Processing Unit) 22 and a display 23 including a liquid crystal display cell for displaying the detection result are provided.

In the above configuration, the printed board 10 is set on the board mounting portion of the circuit board inspection machine, and the center check pin 12e and the peripheral check pins 12a to 12e are set.
d is brought into contact with the corresponding misregistration detection pattern 11. Then, the switch S in the switch circuit 21
W1 to SW4 are sequentially switched. When all of them are electrically connected to the center check pin 12e, it is determined that there is no displacement because each of the check pins 12a to 12d is properly in contact with the displacement detection pattern 11.

On the other hand, when there is no conduction between the center check pin 12e and the peripheral check pin 12d, FIG.
As shown in (a), it is determined that the printed circuit board 10 is shifted in the left direction (arrow X method) in FIG. Central check pin 12e and peripheral check pin 12b
If there is no electrical connection, it is determined that the printed circuit board 10 is displaced in the right direction in FIG.

When the center check pin 12e and the peripheral check pin 12a are non-conductive, the printed circuit board 10 is moved downward (arrow Y method) as shown in FIG. 5B. It is determined that it is shifted. When the center check pin 12e and the peripheral check pin 12c are non-conductive, it is determined that the printed circuit board 10 is displaced in the downward direction in FIG.

Further, when the peripheral check pins 12a and 12d are non-conductive with respect to the central check pin 12e,
As shown in FIG. 5C, the direction of displacement of the printed circuit board 10 in FIG. 5C is a diagonally lower left direction with respect to the origin of the XY axis. When the peripheral check pins 12b and 12c are non-conductive with respect to the center check pin 12e, the shift direction of the printed circuit board 10 in FIG.
That is, the direction is obliquely upper right with respect to the origin of the Y axis.

Similarly, when the peripheral check pins 12a and 12b are non-conductive with respect to the central check pin 12e,
The shift direction of the printed circuit board 10 is determined to be obliquely lower right. When the peripheral check pins 12c and 12d are non-conductive with respect to the central check pin 12e, the printed circuit board 10
Is determined to be a diagonally upper left direction.

At the time of detecting the displacement in the oblique direction, if the conduction and non-conduction states between the check pins are the same for the two displacement detection patterns 11a and 11b, the printed circuit board 10 moves parallel to the circuit board inspection machine. However, as illustrated in FIG. 6, the peripheral check pins 12b and 12c are electrically connected to the central check pin 12e and the peripheral check pins 12a and 12d is non-conducting, while the other misregistration detection pattern 11b has a center check pin 12e and a peripheral check pin 1e.
2a, 12d are conductive, peripheral check pins 12b, 12c
Is non-conducting, it is determined that the printed circuit board 10 is rotated counterclockwise by an angle θ with respect to the circuit board inspection machine.

It should be noted that one of the displacement detection patterns 11a
With respect to the central check pin 12e, the peripheral check pins 12a and 12d conduct,
b and 12c are non-conducting, while the other misregistration detection pattern 11b is the center check pin 12e.
When the peripheral check pins 12b and 12c are conductive and the peripheral check pins 12a and 12d are nonconductive,
The direction of the displacement due to the rotation of the printed circuit board 10 will be referred to as clockwise.

In the above embodiment, the position shift detection pattern 1
1 is a square, but the misalignment detection pattern 11
May be a parallelogram as shown in FIG. 7 (a), a cross shape as shown in FIG. 7 (b), an octagon as shown in FIG. 7 (c), or a circle as shown in FIG. 7 (b).

In the above embodiment, the central check pin 1
Although four peripheral check pins 12a to 12d are arranged for 2e, three peripheral check pins 12a to 12c may be provided as shown in FIG. In this case, assuming that the misregistration detection pattern 11 is a regular square, the peripheral check pin 12a is arranged substantially at the center of one side in FIG.
FIG. 12B shows an example in which the peripheral check pins 12c are arranged at both corners of the opposite side.
A state in which a to 12c are arranged 180 degrees rotationally symmetric is illustrated.

FIG. 9 shows peripheral check pins 12a to 12a.
3 shows a modified example in which the position shift detection pattern 11 is an equilateral triangle in addition to the three lines c. In this case, each of the peripheral check pins 12a to 12c is disposed at a substantially central portion of each side of the position shift detection pattern 11, but in FIGS. The arrangement of the peripheral check pins is also symmetrical by 180 degrees.

That is, when at least one pair of the displacement detection patterns 11 is arranged along the diagonal line of the circuit board 10 to be inspected, if one of them is arranged as shown in FIGS. 8B and FIG. 9B are preferable in terms of detection accuracy.

[0040]

As described above, according to the present invention,
Forming a misregistration detection pattern having a predetermined area in a blank portion of the circuit board to be inspected in a solid color form, and, on the circuit board inspection machine side, one center check pin contacting substantially the center of the misregistration detection pattern; Providing a plurality of peripheral check pins that respectively contact different parts of the periphery of the misregistration detection pattern, and checking conduction / non-continuity between the center check pin and each peripheral check pin to thereby check the circuit board to be inspected with respect to the circuit board inspection machine. The presence / absence of displacement can be detected very easily and reliably.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a printed circuit board as a circuit board to be inspected in the present invention.

FIG. 2 is a schematic diagram showing a correspondence relationship between a misregistration detection pattern on the printed board and a center check pin and a peripheral check pin provided on the circuit board inspection machine side.

FIG. 3 is a schematic diagram showing an electrical connection relationship between a central check pin and each peripheral check pin.

FIG. 4 is a schematic block diagram of a displacement detection device according to the present invention.

FIG. 5 is an explanatory diagram of an operation when detecting a shift direction according to the present invention.

FIG. 6 is a diagram illustrating an operation when detecting a shift in a rotation direction according to the present invention.

FIG. 7 is a plan view showing a modified example of the displacement detection pattern.

FIG. 8 is an explanatory view of a modified example in which each peripheral check pin has three pins.

FIG. 9 is an explanatory diagram of a modified example in which three peripheral check pins are used and a misregistration detection pattern is a triangle.

FIG. 10 is a side view schematically showing an example of a circuit board inspection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Printed circuit board 11, 11a, 11b Position shift detection pattern 12a-12d Peripheral check pin 12e Central check pin SW1-SW4 Switch 21 Switch circuit 22 CPU 23 Display

Claims (6)

[Claims] When a circuit board to be inspected is placed on a board mounting portion of a circuit board inspecting machine and the quality of the circuit board to be inspected is inspected, the position of the circuit board to be inspected is shifted with respect to the board mounting portion. In the position shift detecting device for detecting the presence or absence of the one, a central check arranged so as to contact substantially the center of the position shift detection pattern formed in a solid color with a predetermined area on the circuit board to be inspected side. A plurality of peripheral check pins arranged so as to be in contact with the pins and different portions on the periphery of the misregistration detection pattern,
A switch circuit for connecting one of the plurality of peripheral check pins to the central check pin while switching the plurality of peripheral check pins in a predetermined order; controlling the switching of the switch circuit; A control unit for detecting the presence / absence of a position shift of the circuit board to be inspected due to conduction or non-conduction between the circuit boards. 2. The circuit board according to claim 1, wherein the number of the peripheral check pins is three or more, and the peripheral check pins are arranged at equal angular intervals around the central check pin. A device for detecting displacement during inspection. 3. A circuit board on which a predetermined wiring pattern is formed (a circuit board to be inspected) is placed on a substrate mounting portion of a circuit board inspecting machine, and the quality of the circuit board is inspected. When a misregistration detection pattern having a predetermined area is formed in a blank area in a solid color, and the circuit board to be inspected is placed at an appropriate position of the board placing section on the circuit board inspecting machine side. Wherein one central check pin contacting a substantially central portion of the misregistration detection pattern and a plurality of peripheral check pins respectively contacting different portions of the periphery of the misregistration detection pattern are provided. In the circuit board inspection, the presence / absence of the displacement of the circuit board to be inspected is detected by conducting / non-conducting with a check pin. Position shift detection method. 4. The method according to claim 3, wherein the misregistration detection pattern is circular or polygonal, and the number of the peripheral check pins is three or more. 5. At least one pair of the misregistration detection patterns is arranged along a diagonal line of the circuit board to be inspected, and the central check pin and the central check pin are arranged on the circuit board inspection machine side for each misregistration detection pattern. Multiple peripheral check pins are assigned, and conduction and non-conduction between those central check pins and peripheral check pins
5. The method according to claim 3, wherein the presence / absence of a positional displacement of the circuit board to be inspected with respect to the substrate mounting portion is detected. 6. When arranging at least one pair of the displacement detection patterns along a diagonal line of the circuit board to be inspected, if the displacement detection pattern is an odd-numbered polygon, each of the displacement detection patterns is rotated by 180 degrees. 6. The method according to claim 5, wherein the positions are symmetrically arranged.