JP3418720B2 - Substrate inspection device and substrate inspection method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a board inspection device and a board inspection method for inspecting an electronic circuit board by bringing the tip of a probe pin into contact with an inspection pad provided on the electronic circuit board. .

[0002]

2. Description of the Related Art As a conventional example of the above-mentioned board inspection apparatus, there is one disclosed in Japanese Patent Application Laid-Open No. 3-195981. FIG. 8 is a side view of essential parts for explaining the operation of the board inspection apparatus. The electronic circuit board 43 to be inspected is configured by soldering the electronic component 47 to the conductor pattern 45 formed on the surface thereof. Such an electronic circuit board 43 is mounted on a movable table 46 which is vertically movable in the board inspection apparatus. A plurality of probe pins 41 and a vibrating section 44 are provided on the pin board 42 provided so as to face the movable table 46. Each probe pin 41 is electrically connected to a control unit (not shown) that measures a signal.

In the above conventional board inspection apparatus, the electronic circuit board 4
In order to perform inspection No. 3, first, the electronic circuit board 43 to be inspected is placed on the movable table 46. Then, the movable table 46 is moved upward so as to approach the pin board 42, and the tip of the probe pin 41 is brought into contact with the surface of the inspection pad (not shown) formed on the conductor pattern 45. However, on the surface of the electronic circuit board 43, an impurity layer 48 made of a flux during soldering, an oxide film of solder, or the like may be formed. Therefore, the electrical contact between the inspection pad and the probe pin 41 is not always sufficient merely by bringing the probe pin 41 into contact with the surface of the inspection pad in this manner. Therefore, the vibrating portion 44 is operated in a state where the tip of the probe pin 41 is in contact with the surface of the inspection pad, and the probe pin 41 is vibrated. Then, the impurity layer 48 is scraped off at the tip of the vibrating probe pin 41, so that the probe pin 41 and the inspection pad are surely brought into contact with each other. Then, an electric signal is transmitted from the inspection pad to the controller via the probe pin 41, and it is possible to determine whether the electronic circuit board 43 is a good product or not based on the transmitted electric signal.

[0004]

In recent years, in electronic circuit boards, extremely small electronic components 47 are used and conductor patterns 45 are also formed extremely finely in response to the demand for compactness of equipment. ing. Therefore, the inspection pad formed on the conductor pattern 45 is inevitably in a very small area. When the inspection pad has such a small area, it becomes difficult to accurately match the tip position of the probe pin 41 with the position of the inspection pad. Therefore, the probe pin 41 does not need to be raised just by raising the movable table 46.
It is becoming difficult to bring the tip of the abutment into contact with the surface of the inspection pad. Certainly, if the above-mentioned conventional substrate inspection apparatus is used, the impurity layer 48 is not formed at the tip of the probe pin 41.
Is stripped. Thus, the contact between the probe pin 41 and the inspection pad can be ensured. However, such reliable contact between the probe pin 41 and the inspection pad is premised on the fact that the tip position of the probe pin 41 and the position of the inspection pad exactly match in advance before the impurity layer 48 is removed. There is. Therefore, in the recent inspection of an electronic circuit board in which it is difficult to accurately match the tip position of the probe pin 41 and the position of the inspection pad, even if the conventional board inspection device is used, It is not easy to make reliable contact with the pad. If the contact between the probe pin 41 and the inspection pad becomes uncertain in this way, an erroneous inspection may occur and the reliability of the substrate inspection and the production rate may decrease.

The present invention has been made to solve the above-mentioned conventional problems, and its object is to provide an inspection pad formed on an electronic circuit board to be inspected having an extremely small area. Another object of the present invention is to provide a substrate inspection device and a substrate inspection method capable of reliably contacting a probe pin with an inspection pad to perform a highly reliable substrate inspection.

[0006]

In view of the above, the board inspection apparatus according to the first aspect of the present invention inspects the electronic circuit board by bringing the tip of the probe pin into contact with an inspection pad provided by being recessed from the surface of the electronic circuit board. A board inspecting device for performing, wherein an elastic body that applies an elastic force toward the tip side of the probe pin, a pressing unit that presses the tip of the probe pin near the inspection pad of the electronic circuit board, and the pressed A vibrating means for applying relative vibration having a component parallel to the substrate surface is provided between the probe pin and the electronic circuit substrate.

Further, the board inspecting method according to claim 4 is a board inspecting method for inspecting the electronic circuit board by bringing the tip of the probe pin into contact with an inspection pad provided by being recessed from the surface of the electronic circuit board. Then, an elastic force is applied to the probe pin toward the tip side thereof, and a pressing process of pressing the probe pin to the vicinity of the inspection pad of the electronic circuit board, and the probe pin and the electronic device pressed in the pressing process. A vibration process for applying relative vibration having a component parallel to the substrate surface is provided between the circuit substrate and the circuit substrate.

In these board inspection apparatuses or board inspection methods, relative vibration having a component parallel to the board surface is applied between the probe pin pressed near the inspection pad of the electronic circuit board and the electronic circuit board. . When such relative vibration is applied, the relative position between the tip of the probe pin and the electronic circuit board, which are not accurately pressed against the location of the inspection pad, slightly changes. When the tip of the probe pin moves to the position opposite to the inspection pad, the tip of the probe pin to which the elasticity is applied is pressed by the recessed inspection pad, and further movement in the direction parallel to the substrate surface causes the inspection. Is blocked by the periphery of the pad. Therefore, the tip of the probe pin can be surely brought into contact with the inspection pad.

Further, according to a second aspect of the board inspection apparatus, the probe pins are provided in plural on the probe pin support member corresponding to each of the plurality of inspection pads provided on the electronic circuit board, and each probe pin is , The tip end of which is attached to the probe pin support member such that the tip end of the probe pin support member has a component parallel to the substrate surface and is swingable independently of each other. It is characterized in that it is configured to be added between the electronic circuit board and the electronic circuit board.

According to another aspect of the substrate inspection method of the present invention, a plurality of the probe pins are provided on the probe pin support member corresponding to each of the plurality of inspection pads provided on the electronic circuit board, and each probe pin is The tip has a component parallel to the substrate surface and is attached to the probe pin support member so as to be independently swingable, while the relative vibration is applied to the probe pin support member and the electron in the excitation process. It is characterized in that it is added to the circuit board.

In these board inspection devices or board inspection methods, the tips of the plurality of probe pins pressed against the electronic circuit board have a component parallel to the board surface due to the relative vibration applied to the probe pin support member. Each swings independently. Therefore, even if the probe pins and the inspection pad are not provided so as to face each other accurately even though the structure is simple, the tip of each probe pin is opposed to the inspection pad by the independent swing. To position
It is possible to surely bring the tips of all the probe pins into contact with the inspection pad.

The board inspection apparatus according to a third aspect of the invention is characterized in that the vibrating means also applies relative vibration having a component perpendicular to the board surface between the probe pin and the electronic circuit board.

According to a sixth aspect of the present invention, there is provided a substrate inspection method, wherein in the vibrating process,
The feature is that a relative vibration having a component perpendicular to the substrate surface is also applied.

In these board inspection apparatuses or board inspection methods, relative vibration having a component perpendicular to the board surface is also applied between the probe pin pressed in the vicinity of the inspection pad of the electronic circuit board and the electronic circuit board. There is. Therefore, even when unevenness is formed on the surface of the electronic circuit board, it is possible to reliably move the probe pin to a position facing the inspection pad by overcoming these unevenness.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, specific embodiments of the substrate inspection apparatus and the substrate inspection method of the present invention will be described in detail with reference to the drawings.

FIG. 7 is a perspective view showing the appearance of the entire board inspection apparatus. The movable table 4 is vertically movable by a drive mechanism 5. Then, the electronic circuit board 3 to be inspected is positioned and placed at a predetermined position on the movable table 4. A pin board (probe pin support member) 2 is arranged so as to face the movable table 4. A vibration unit (vibration means) 8 and a plurality of probe pin assembly members 18, which will be described later, are attached to the pin board 2.
The wiring extending from the probe pin assembly member 18 is connected to the control unit 7 via the cable 6.

On the other hand, FIG. 6 is a sectional view showing the inspection pad 9 provided on the electronic circuit board 3. In this electronic circuit board 3, a resist 10 made of an insulator is formed thin so as to cover the surface thereof. Then, as shown in FIG. 3A, the resist 10 is removed at the portion where the inspection pad 9 is provided, and the inspection pad 9 made of a conductor is exposed on the surface of the electronic circuit board 3. There is. Therefore, the inspection pad 9 is provided so as to be recessed from the surface of the electronic circuit board 3.

FIG. 3 is a transparent side view showing the structure of the probe pin assembly member 18. In this probe pin assembly member 18, the probe pin 1 is inserted into a bottomed cylindrical socket 11 having an opening on one side ((a) in the figure), and the sharp tip of the probe pin 1 is opened on the socket 11. It is exposed from the edge ((b) of the same figure). A spring 12 is built as an elastic body in the probe pin 1.
The tip of the probe pin 1 can be moved up and down by expanding and contracting 2. Further, the probe pin assembly member 18 is
As shown in the side view of FIG. 4, the intermediate portion of the socket 11 is pivotally supported on the pin board 2 by the support shaft 13, and the tip of the probe pin 1 is attached so as to be freely swingable. On the other hand, the electronic circuit board 3 is provided with a plurality of inspection pads 9 as shown in the schematic perspective view of FIG. Therefore, a plurality of the probe pin assembly members 18 are provided on the pin board 2 so that the inspection pads of the electronic circuit board 3 mounted on the movable table 4 and the probe pins 1 face each other. ing.

FIG. 5 is a side view showing the structure of the vibrating section 8 provided on the pinboard 2. The vibrating section 8 includes a motor 14 and an eccentric weight 16 attached to a rotating shaft 15 of the motor 14. The action of the eccentric weight 16 rotating eccentrically causes vibration along a plane perpendicular to the rotating shaft 15. The pin board 2 has the rotating shaft 15 perpendicular to the board surface of the electronic circuit board 3 mounted on the movable table 4.
The vibrating section 8 is provided such that Therefore, the vibrating portion 8 applies vibration to the pinboard 2 in a direction (= parallel direction) along the board surface of the electronic circuit board 3. When such a vibration is applied to the pin board 2, the probe pin assembly member 18 in which the probe pin 1 is inserted is attached to the pin board 2, so that each probe pin 1 together with the pin board 2 is attached. It will vibrate. Moreover, as described above, the probe pin assembly member 18 is attached to the pin board 2 so that the tip of the probe pin 1 can swing. Therefore, due to the vibration, the tip of each probe pin 1 has a component parallel to the substrate surface and swings independently, as shown by the arrow in FIG.

Next, a board inspection method performed by using the board inspection apparatus will be described. First, the electronic circuit board 3 to be inspected is placed on the movable table 4 with the inspection pad 9 facing upward. In this state, the tip of the probe pin 1 and the electronic circuit board 3 are separated from each other. Therefore, the spring 12 provided in the probe pin assembly member 18 is in a free state in which it is balanced with the weight of the probe pin 1 as shown in FIG. From this state, the drive mechanism 5 is operated to raise the movable table 4 to the pinboard 2 side. Then, the tip of the probe pin 1 is brought into contact with the surface of the electronic circuit board 3, and the drive mechanism 5 is further operated to bring the pin board 2 and the electronic circuit board 3 close to each other. Then, the probe pin 1 is pushed up by the electronic circuit board 3 as shown in FIG.
2 is shortened so that the probe pin 1 is given an elastic force toward its tip side.

The probe pins 1 are provided so as to face the inspection pads 9 of the electronic circuit board 3 positioned and mounted on the movable table 4. Therefore, when the drive mechanism 5 is operated as described above, the tip of the probe pin 1 is pressed near the inspection pad 9. That is, the movable table 4 for positioning and mounting the electronic circuit board 3
Also, the drive mechanism 5 constitutes a pressing means for executing the pressing process. Then, the vibrating portion 8 is operated in this state, and in the vibrating process, relative vibration having a component parallel to the substrate surface is generated between the probe pin 1 and the electronic circuit substrate 3.

The inspection pad 9 has an extremely small area in order to meet the demand for downsizing the electronic circuit board 3. Therefore, it is difficult to accurately position the tip of the probe pin 1 on the inspection pad 9 only by raising the movable table 4. Most of the resists 10 are formed on the surface of the electronic circuit board 3 as shown by the dashed line in FIG.
And the tip of the probe pin 1 come into contact with each other. In this state, when relative vibration having a component parallel to the substrate surface is applied between the probe pin 1 and the electronic circuit board 3, the tip of the probe pin 1 moves on the surface of the electronic circuit board 3. When the tip of the probe pin 1 is positioned on the inspection pad 9, the probe pin 1 is elastically exerted by the spring 12, so that the tip of the probe pin 1 contacts the inspection pad 9 as shown by the solid line in FIG. It will be pressed. Since the inspection pad 9 is recessed from the surface of the electronic circuit board 3, even if the relative vibration is further applied from this state, the probe pin 1 does not move in the direction along the board surface of the resist 10. The inspection pad 9 is blocked by the edge portion 10a.
You can't get out of the top. Therefore, even if the inspection pad 9 is formed in an extremely small area, the probe pin 1 can be surely brought into contact with the inspection pad 9.
Then, an electric signal is transmitted from the inspection pad 9 to the control unit 7 via the probe pin 1, and the control unit 7 analyzes whether or not the electronic circuit board 3 is a good product based on the transmitted electric signal. is there. Therefore, according to the board inspection method using this board inspection apparatus, it is possible to perform an extremely reliable board inspection.

As described above, the resist 10 is removed at the portion of the electronic circuit board 3 where the inspection pad 9 is located. However, since the resists formed on the substrates of the individual electronic circuit boards 3 are misaligned, in some of the inspection pads 9, the resist 10 protrudes onto the inspection pads 9 as shown in FIG. 6B. May have been formed. Further, when the inspection pad 9 has an extremely small area, it is difficult to dispose all the probe pins 1 so as to exactly face the inspection pad 9, respectively. In such a case, probe pin 1
Are fixed to the pin board 2, the pin board 2 is vibrated and some of the probe pins 1 are moved to the inspection pad 9 due to the protruding placement error of the resist 10 and the probe pin 1. Even if you can make contact
There is a problem that the remaining probe pins 1 cannot be brought into contact with the inspection pad 9 by any means. However, in the above-described board inspection device, the tip end of each probe pin 1 independently swings parallel to the board surface due to the vibration applied by the vibrating section 8. Therefore, even in the above case, each probe pin 1 swings, and the tips of all the probe pins 1 can be positioned on the inspection pad 9, respectively. Therefore, according to the same principle as described above, all the probe pins 1 can be surely brought into contact with the inspection pads 9, and thereby a more highly reliable substrate inspection can be performed. And in this case, the support shaft 1
A plurality of probe pin assembly members 18 are pivotally supported on the pin board 2 by means of 3, and relative vibration is applied between the pin board 2 and the electronic circuit board 3. Therefore, the tip of each probe pin 1 can be independently rocked by a single vibration unit 8,
As a result, the structure of the inspection device can be made extremely simple.

Further, the amplitude of the tip of the probe pin 1 due to the relative vibration including the above-mentioned oscillation is larger than the maximum error that can occur between the arrangement position of the inspection pad 9 and the attachment position of the probe pin 1, and Inspection pads 9 adjacent to each other
It is desirable to be smaller than the minimum distance between. When the amplitude is smaller than the maximum error between the arrangement position of the inspection pad 9 and the attachment position of the probe pin 1, the probe pin 1 may not be reliably positioned at the position facing the inspection pad 9, Further, the inspection pads 9 having the amplitudes adjacent to each other
This is because if the distance is larger than the minimum distance, the probe pins 1 may come into contact with the adjacent inspection pads 9 that should not be in contact with each other.

Although the specific embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. In the above description, the vibration unit 8 applies the relative vibration having a component parallel to the substrate surface between the probe pin 1 and the electronic circuit board 3, but further applies the relative vibration having a component perpendicular to the substrate surface. You may do it. In order to apply such relative vibration between the probe pin 1 and the electronic circuit board 3, the second vibrating section arranged so that the rotary shaft 15 of the motor 14 extends in the direction along the board surface is provided. You can add it to the pin board 2. With this configuration, the vibration applied to the socket 11 by the second vibrating section is transmitted to the probe pin 1 via the spring 12 and is perpendicular to the board surface between the probe pin 1 and the electronic circuit board 3. A relatively small amplitude relative vibration with a component can be applied. Then, even when unevenness of the resist 10 is formed on the surface of the electronic circuit board 3, the peak 17 of the unevenness is formed on the probe pin 1 by the relative vibration.
(See FIG. 1) and can be reliably positioned on the inspection pad 9.

In this case, the amplitude of the relative vibration applied between the probe pin 1 and the electronic circuit board 3 in the direction perpendicular to the board surface is smaller than the recessed amount of the inspection pad 9. Is desirable. If the relative vibration has such an amplitude, the probe pin 1 located on the inspection pad 9
The movement in the direction along the substrate surface is surely blocked by the edge portion 10a of the resist 10. Therefore, the tip of the probe pin 1 will continue to be stably positioned on the inspection pad 9 even if relative vibration in the vertical direction is applied. The amount of unevenness formed on the surface of the resist 10 is usually smaller than the thickness of the resist 10, that is, the amount of depression of the inspection pad 9. Therefore, it is possible to cause the probe pin 1 to pass over the mountain portion 17 by the relative vibration having the above-described amplitude, and to reliably position the mountain portion 17 on the inspection pad 9.

Further, in the above, the vibrating section 8 vibrates the pin board 2, and thereby the relative vibration is applied between the probe pin 1 and the electronic circuit board 3. However, this may be arranged such that the vibrating section 8 is provided on the movable table 4 side to vibrate the electronic circuit board 3, whereby relative vibration is applied between the probe pin 1 and the electronic circuit board 3. Further, in the above, the probe pin assembly member 18 is rotatably supported by the support shaft 13, so that the tip of the probe pin 1 can be swung in one direction. However, it is also possible to support the probe pin assembly member 18 by using, for example, a bearing so that the tip of the probe pin 1 can swing in multiple directions. Although the spring 12 is used as the elastic body in the above description, it may be an air spring or another elastic body such as rubber, as a matter of course.

Further, in the above, the substrate inspection apparatus in which the movable table 4 is movable in the vertical direction by the drive mechanism 5 is shown. However, pin board (probe pin support member)
2 may be moved in the vertical direction so that the tip of the probe pin 1 and the inspection pad 9 can be brought into contact with each other. Further probe pin 1
The tip does not have to point downwards. For example, a configuration in which the tip of the probe pin 1 faces upward, or a configuration in which one board inspection device has probe pins 1 facing upward and downward, and an electronic circuit board 3 can be sandwiched for inspection It doesn't matter.

Further, in the above, the intermediate portion of the socket 11 is pivotally supported by the support shaft 13, whereby the probe pin 1
The tip of the can swing freely. However, for this, for example, the probe pin assembly member 18 may be configured as follows so that the tip of the probe pin 1 can freely swing. That is, the inner diameter of the socket 11 is set to be slightly larger than the outer diameter of the probe pin 1,
A gap is formed between the inner peripheral surface of the socket 11 and the outer peripheral surface of the probe pin 1. Then, the socket 11 is attached to the pin board 2 by, for example, press fitting. Also with such a configuration, each probe pin 1 can be independently swung by the vibration applied to the socket 11. In this case, since the structure is extremely simple, the cost of the substrate inspection device can be reduced.

[0030]

As described above, in the board inspecting apparatus of the first aspect or the board inspecting method of the fourth aspect, the board surface is provided between the probe pin pressed near the inspection pad of the electronic circuit board and the electronic circuit board. By applying relative vibration having a parallel component, the tip of the probe pin can be surely brought into contact with the inspection pad provided by being recessed from the substrate surface. Therefore, even when the inspection pad is formed in an extremely small area, it is possible to reliably bring the probe pin into contact with the inspection pad and perform a highly reliable substrate inspection.

A substrate inspection apparatus according to claim 2 or claim 5
In the board inspection method of 1, even when the plurality of probe pins and the inspection pad are not provided to face each other accurately, the tips of all the probe pins are surely brought into contact with the inspection pad by a simple configuration. be able to. Therefore, even when it is necessary to bring a plurality of probe pins into contact with a plurality of inspection pads, it is possible to perform reliable board inspection by ensuring contact between the probe pins and the inspection pad while reducing costs. It will be possible.

Further, in the board inspection apparatus of claim 3 or the board inspection method of claim 6, even when the surface of the electronic circuit board is formed with irregularities, the probe pin is surely placed on the inspection pad. It can be moved. Therefore, more surely contact the probe pin with the inspection pad,
It is possible to perform a more reliable board inspection.

[Brief description of drawings]

FIG. 1 is a transparent side view for explaining an operation of a probe pin provided in a substrate inspection device according to an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a positional relationship between the probe pin and an electronic circuit board.

FIG. 3 is a transparent side view showing a configuration of a probe pin assembly member including the probe pin.

FIG. 4 is a side view showing a mounting structure of the probe pin assembly member.

FIG. 5 is a side view showing a configuration of a vibrating section provided in the board inspection apparatus.

FIG. 6 is a cross-sectional view showing the vicinity of an inspection pad of an electronic circuit board to be inspected.

FIG. 7 is a perspective view showing an appearance of the entire substrate inspection apparatus.

FIG. 8 is a side view of an essential part for explaining the operation of the conventional board inspection apparatus.

[Explanation of symbols]

1 probe pin 2 pin board 3 Electronic circuit board 5 Drive mechanism 8 Vibration part 9 Inspection pad 12 spring

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Claims (6)

(57) [Claims] 1. A board inspection device for inspecting the electronic circuit board by bringing the tip of a probe pin into contact with an inspection pad that is recessed from the surface of the electronic circuit board, the tip being attached to the probe pin. An elastic body that applies an elastic force toward the side, a pressing unit that presses the tip of the probe pin near the inspection pad of the electronic circuit board, and between the pressed probe pin and the electronic circuit board, parallel to the board surface. And a vibrating means for applying relative vibration having various components. 2. A plurality of the probe pins are provided on a probe pin support member corresponding to each of a plurality of inspection pads provided on an electronic circuit board, and each probe pin has a tip on the board surface. The probe pin support member is attached to the probe pin support member so as to be independently swingable with parallel components, while the vibrating means applies the relative vibration between the probe pin support member and the electronic circuit board. 2. The method according to claim 1, wherein
Board inspection device. 3. The vibrating means also applies relative vibration having a component perpendicular to the substrate surface between the probe pin and the electronic circuit substrate.
Board inspection device. 4. A board inspection method for inspecting the electronic circuit board by bringing the tip of a probe pin into contact with an inspection pad provided by being recessed from the surface of the electronic circuit board. While applying an elastic force toward the tip side, a pressing step of pressing this probe pin near the inspection pad of the electronic circuit board, and between the probe pin and the electronic circuit board pressed in this pressing step,
And a step of applying a relative vibration having a component parallel to the substrate surface. 5. A plurality of the probe pins are provided on a probe pin support member corresponding to a plurality of inspection pads provided on an electronic circuit board, and the tip of each probe pin is on the board surface. While being attached to the probe pin support member so as to be independently swingable with parallel components, in the vibrating process, the relative vibration is applied between the probe pin support member and the electronic circuit board. The board inspection method according to claim 4, wherein the board inspection method is added. 6. The substrate according to claim 4, wherein in the vibrating step, relative vibration having a component perpendicular to the substrate surface is also applied between the probe pin and the electronic circuit substrate. Inspection method.