JPH06350226A - Method and apparatus for correcting conductor pattern on printed wiring board - Google Patents

Abstract

PURPOSE:To allow correction of the discontinuity of wirings at a bent part or partial chipping of a mounting pad while improving the external view of corrected conductor pattern. CONSTITUTION:A cathode is brough into contact with a conductor pattern L in which a circuit discontinuity has occurred, for example, and an anode 12 is disposed oppositely to the end face Ha of the conductor pattrn L. A Cu salt solution is then dropped between the end face Ha and the anode 12 and electrolytic plating is conducted between the conductor pattern L having discontinuity and the anode 12 thus forming a conductor pattern. This method allows correction of the conductor pattern by depositing Cu according to the profile of the conductor pattern.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for repairing a conductor pattern of a printed wiring board, and more particularly to a conductor capable of repairing a broken wire of a conductor pattern and a missing pad for mounting electronic parts. The present invention relates to a pattern correction method and a pattern correction device.

[0002]

2. Description of the Related Art When a conductor pattern formed on a printed wiring board has a defect such as a disconnection, the conductor pattern is usually not modified in order to maintain high reliability. However, in recent years, in a printed wiring board on which a large and complicated electronic component such as VLSI is mounted, since the wiring board itself is expensive, it is costly to completely replace it even if a defect occurs in only one place. The burden will be very heavy. Therefore, the conductor pattern may be modified within the range in which electrical and mechanical reliability can be guaranteed according to the customer's request.

Conventionally, a method of using a fine metal wire (diameter of about 100 to 200 μm) such as Au or Cu has been carried out as a method of correcting the disconnection of the wiring portion of the conductor pattern.

[0006] As shown in FIG. 7, first, a wire without wire 31 having a width substantially the same as that of the wire 30 (for example, a metal wire having a diameter of 100 μ with respect to a wire width of 100 μ) and both ends of the wire 30 which have been disconnected. The length is set to cover 30a and 30b. Then, after the broken portion of the wiring 30 is washed with a cleaning liquid, the metal thin wire 31 is placed at a position to be corrected of the wiring 30, and then both ends thereof and both ends 30a and 30b of the wiring are electrically welded. After that, it is confirmed that the fine metal wire 31 is correctly aligned with the wiring 30 and that the welding is performed well, and the repaired portion is wiped with a solvent or the like to complete the repair.

[0005]

However, the above-described method of repairing a conductor pattern has a problem in that it is impossible to repair a broken wire at a bent portion of a wiring or a partial loss of a mounting pad.

That is, the breakage of the bent portion can be corrected by bending the thin metal wire into a shape suitable for the bent portion. However, since the bent portion of the thin metal wire is not sufficiently strong, it is bent. It is not possible to guarantee the long-term mechanical reliability of processed metal wires. Therefore, in terms of reliability, the conductor pattern cannot be modified. Further, since the mounting pad is formed in a rectangular shape or the like, when a partial defect occurs, the defect has a concave shape. Therefore, even if a thin metal wire is used, such a defect cannot be properly corrected because the correction area is large. For this reason, if the above-mentioned disconnection or defect occurs even at one place, it cannot be corrected, and the current situation is that the replacement is complete.

Further, in the correction method using the fine metal wire, the fine metal wire and the conductor pattern are welded in a state of being overlapped with each other, so that the fine metal wire is raised on the conductive pattern after the correction. For this reason, there is not only a problem of impairing the appearance of the conductor pattern after the correction, but also a problem that mounting is hindered particularly due to the swelling of the mounting pad.

The present invention has been made in order to solve the above-mentioned problems, and an object thereof is to correct a disconnection of a bent portion of a wiring and a partial loss of a mounting pad, and It is an object of the present invention to provide a method and a device for correcting a conductor pattern of a printed wiring board, which can improve the appearance of the conductor pattern after correction.

[0009]

In order to solve the above-mentioned problems, in the method according to claim 1, the cathode is brought into contact with the conductor pattern having a disconnection and the anode is arranged at a position facing the end face of the conductor pattern. Then, after dropping the electrolytic solution between the end surface and the anode, electrolytic plating is performed between the anode and the conductor pattern in which disconnection or the like has occurred to form the conductor pattern.

Further, in the apparatus according to the second aspect, an anode for electrolytic plating, an arranging means for arranging the anode at a position opposed to an end surface of the printed wiring board in which a conductor pattern of the printed wiring board is broken, and the arrangement. Dropping means for dropping the electrolytic solution between the anode and the end face in a state where the anode is arranged by the means, and a conductor pattern in which a disconnection occurs with the anode in the dropping state of the electrolytic solution. And a voltage applying means for applying a voltage between them.

[0011]

In the method of the present invention, the cathode is brought into contact with the conductor pattern of the printed wiring board where the wire is broken, the anode is arranged at a position facing the end face, and the electrolytic solution is dripped between the end face and the anode. Electrolytic plating is performed in this state. Therefore, even for the disconnection of the bent portion of the wiring of the conductor pattern, electrolytic plating is performed according to the bent shape,
The disconnection is corrected. Similarly, with respect to the defect of the component pad for mounting, electrolytic plating is performed according to the shape of the defect end face to correct the defect. Further, unlike the modification of the thin metal wire by electric welding, the conductor pattern does not rise, and the appearance of the modified conductor pattern is improved.

According to the second aspect of the present invention, the arranging means arranges the electrolytic plating anode at a position facing the end face where the conductor pattern of the printed wiring board is broken. The dropping means drops the electrolytic solution between the anode and the end face in a state where the anode is arranged. The applying means applies a voltage between the anode and the conductor pattern in which the disconnection or the like has occurred while the electrolytic solution has been dropped. Then, as the plating layer is gradually formed from the end face of the conductor pattern, the anode is moved to form a pattern having a predetermined shape corresponding to the disconnection of the bent portion of the wiring and the loss of the component pad.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to FIGS. As shown in FIG. 2, the correction apparatus of this embodiment has a moving system 1 for moving the printed wiring board P and an observation system 2 for observing the conductor pattern L of the printed wiring board P.
And a correction system 3 for correcting the conductor pattern L.

The moving system 1 has a support shaft 4, and the support shaft 4
Is attached to a base (not shown) so as to be movable in vertical and horizontal directions and rotatable. A stage 5 as a rectangular holding means is fixed to the upper end of the support shaft 4 so as to be horizontal, and a printed wiring board P is mounted on the stage 5. The printed wiring board P can be moved along with the support shaft 4 in the vertical and horizontal directions at a predetermined speed and can be rotated about the support shaft 4 by operating an operation unit (not shown).

The observation system 2 comprises a microscope main body 8 having an objective lens 6 and an eyepiece lens 7. The microscope main body 8 is connected and supported at a position where the objective lens 6 faces the printed wiring board P so as to be vertically movable via a connecting member 9 to a column (not shown). Further, an adjusting knob 10 for adjusting the focus is rotatably attached to the connecting member 9, and by rotating the adjusting knob 10, the microscope main body 8 is moved up and down, so that the printed wiring board P is The focus can be adjusted with respect to the conductor pattern.

As shown in FIG. 1 and FIG. 2, the correction system 3 is a glass capillary 1 as a dropping means for dropping a plating solution made of Cu salt on the broken portion of the conductor pattern L.
1 and an anode 12 made of a Cu-P alloy. The tip end 11a of the capillary 11 is formed in a taper shape, and its base end side is inserted and supported by a holder 13 provided in the microscope body 8. The tip 11a of the capillary 11 is always positioned within the field of view of the eyepiece lens 7. Further, the capillary 11 is the holder 1
By rotating the adjusting screw 14 provided in 3,
It can move up and down while being supported, and can be moved toward and away from the conductor pattern L. Further, one end of a flexible tube 15 is externally fitted to the base end of the capillary 11, and a storage tank 16 for storing Cu salt is suspended from the other end of the flexible tube 15 by a suspending tool (not shown). There is. Then, by opening a cock (not shown) of the storage tank 16, the stored Cu salt is dropped from the tip 11a of the capillary 11 to the disconnection portion of the conductor pattern L via the flexible tube 15 at predetermined intervals. There is.

The anode 12 is formed in a rectangular shape corresponding to the width and thickness of the wiring H of the conductor pattern L, and one end of a support bar 17 supporting the anode 12 is welded and fixed to one end thereof. The support bar 17 is formed in a substantially V shape, and the other end side is inserted and supported by a holder 18 as an arrangement means provided in the microscope body 8. And
The anode 12 is always supported by the support bar 17 and is positioned within the visual field of the eyepiece lens 7. Further, the support bar 17 is moved up and down in a supported state by rotating an adjusting screw 19 as an arrangement means provided in the holder 18, and the anode 12 is located at a position facing the disconnection end face Ha of the wiring H. It can be placed. Further, the end of the support bar 17 is connected via the connecting cord 20 to the plus electrode 2 of the power source 21 which constitutes the applying means for electroplating.
It is connected to 1a. Minus electrode 21b of power supply 21
That is, the cathode is connected to the conductor pattern L having the disconnection via the connection cord 22.

The anode 12 is the end surface Ha of the wiring H.
The Cu salt is dripped onto the disconnection portion D in a state of being separated by a predetermined distance. Further, after the Cu salt is dropped, by applying a constant voltage from the power source 21 between the anode 12 and the wiring H, electrolysis occurs and the anode 12 is melted so that Cu is deposited on the end surface Ha. It has become. Therefore, the anode 12 is replaced with the support bar 17 depending on the degree of melting. Further, the control unit (not shown) of the moving system 1 controls the Cu deposition rate of the conductor pattern L (200 μm / in this embodiment) based on the operation of the operation unit.
The printed wiring board P is moved at a speed according to h). Therefore, the distance between the anode 12 and the Cu deposition surface of the wiring H can always be maintained at a predetermined distance.

In this embodiment, instead of the support bar 17 and the anode 12, as shown in FIG. 4, a rod-shaped anode 24 made of insoluble Pt having a tapered felt 23 adhered to its tip can be replaced. Has become. Then, with the felt 23 of the anode 24 impregnated with Cu salt,
For example, electroplating can be performed on a small gap generated when Cu is deposited from both end surfaces Ha and Hb of the wiring H.

Next, a method of correcting the conductor pattern L will be described by taking the conductor pattern L formed by the full additive method as an example. FIG. 1 shows an example of the wiring H of the conductor pattern L having the bent portion K, and the bent portion K of the wiring H is broken. The portions other than the wiring H are covered with the solder resist S. The length of this disconnection is about 200 μm.

First, after placing the printed wiring board P on the stage 5, the operating portion (not shown) is operated to move the printed wiring board P so that the disconnection portion of the wiring H is located immediately below the objective lens. Subsequently, the operator observes the wiring H through the objective lens 6 of the microscope body 8 and
The printed wiring board P is moved so that the distance between the wiring 2 and the end surface Ha of the wiring H is about 20 μm. Next, the adjusting screw 19 is rotated to move the support bar 17 downward so that the anode 12 is located at a position facing the end surface Ha. Similarly, the adjusting screw 14 is rotated to move the capillary 11 downward so that the tip 11a of the capillary 11 comes close to the wiring H.

Next, a cock (not shown) of the storage tank 16 is opened, and a predetermined amount of Cu salt is dropped from the tip 11a of the capillary 11 between the anode 12 and the end surface Ha. At this time,
Since the Cu salt is blocked by the side wall of the anode 12 and the solder resist S, the anode 12
Hardly protrudes from between the end face Ha and the end face Ha. Then, the support bar 17 is connected to the power source 21 via the connection cord 20.
Connection to the positive electrode 21a of the
It is connected to the negative electrode 21b of the power source 21 via. Then, from the power supply 21 to 1.
Electroplating is performed at a current of 10 A by applying a voltage of 5V. At the same time, the control unit (not shown) of the moving system 1 moves the printed wiring board P at a speed of 200 μm / h based on the operation of the operation unit. Then, when Cu is gradually deposited on the end surface Ha and reaches the bending point T of the bending portion K,
The voltage application from the power source 21 is stopped to suspend the electroplating temporarily.

Next, the adjusting screw 19 is rotated to rotate the support bar 1
7, the anode 12 is moved upward, and the adjusting screw 14 is rotated to move the capillary 11 upward. Then, the anode 12 is connected to another end surface Hb of the wiring H in the same manner as described above.
After moving the printed wiring board P to a position facing with, the anode 12 and the capillary 11 are set at positions where electroplating is performed (FIG. 3). Then, similarly to the above, while a predetermined amount of Cu salt is dropped between the anode 12 and the end surface Hb, a voltage is applied from the power source 21 to perform electroplating. Then, the printed wiring board P is moved until a small gap is formed in the vicinity of the wall surface of the initially deposited Cu to deposit Cu, and then the voltage application from the power source 21 is stopped to stop the electroplating. To do.

Next, the adjusting screw 19 is rotated to rotate the support bar 1
The 7 is replaced by the anode 24 and the felt 23 is positioned in the gap formed by Cu deposited by two electroplatings. Then, from the capillary 11 to the gap
Salt is dropped and a voltage is applied from the power source 21 to perform electroplating. At this time, the adjusting screw 19 is rotated to rotate the anode 2
Electroplating is performed while the felt 23 is brought into contact with the wall surface of Cu while moving 4 up and down. Then, after Cu is deposited in the gap and the wiring H is connected, the voltage application from the power source 21 is stopped and the correction is completed. The time required to correct the wiring H was about one and a half hours.

Next, a method of correcting the defect of the component pad other than the disconnection of the bent portion K of the wiring H as described above will be described. The component pad 25 shown in FIG. 5 is formed in a rectangular shape, and one corner portion C thereof is missing.

First, the printed wiring board P placed on the stage 5 is moved to move the anode 12 to the component pad 25.
It is set at a position substantially parallel to the surface of the defect end surface 25a and having an interval of about 20 μm. Further, the capillary 11 is set at a position where the tip end 11a thereof is close to the component pad 25. Next, a predetermined amount of Cu salt is dropped from the tip 11a of the capillary 11. At this time, the Cu salt is less likely to protrude between the anode 12 and the end surface 25a due to surface tension. Subsequently, a voltage is applied from the power source 21 between the anode 12 and the component pad 25 to perform electroplating. At the same time, based on the operation of the operation unit, 200 μm /
The printed wiring board P is moved at a speed of h. Then, when the deposited Cu approaches the position that becomes the outline 25b of the component pad 25, the side surface of the anode 12 and the outline 25a.
The printed wiring board P is rotated so that and are parallel to each other.
Then, while the anode 12 remains parallel, Cu
When the outermost line 25a is deposited, the voltage application from the power source 21 is stopped and the electroplating is temporarily interrupted. Next, the component pad 25 adjacent to the deposited Cu
The anode 12 is set at a position facing the end surface 25a of the above, and electroplating is performed (FIG. 6). Then, in the same manner as above, after Cu is deposited on all the defective portions, the power source 21
Then, the voltage application from is stopped and the correction of the component pad 25 is completed.

As described above, the conductor pattern L of this embodiment
According to the repairing apparatus and the repairing method, the Cu is gradually deposited on the end surfaces Ha and Hb of the broken wire H by electroplating. Cu can be deposited and corrected according to the bent shape.

Similarly, even if the component pad 25 for mounting is damaged, Cu can be gradually recovered from the defective end surface 25a, so that the original shape can be corrected.

Further, since Cu having the same composition as that of the conductor pattern L is deposited and modified, it is difficult to distinguish the finished state after modification from the conductor pattern L, and the appearance of the conductor pattern can be improved.

Further, since the stage 5 can be moved in the vertical and horizontal directions via the support shaft 4 and further can be rotated about the support shaft 4, the printed wiring board P placed on the stage 5 can be moved. Mobility can be increased. Therefore, even the wiring H having the bent portion K and the component pad 25 having a partial defect can be smoothly electroplated and corrected.

Further, since the printed wiring board P is moved according to the Cu deposition rate during electroplating, the distance between the anode 12 and the Cu deposition surface becomes constant, so that electroplating is efficiently performed. be able to.

Further, by disposing the microscope main body 8 on the stage 5, it is possible to magnify and observe the corrected portion of the conductor pattern L. Therefore, the correct correction is performed while confirming the progress of the correction work. be able to.

The present invention is not limited to the above embodiments, but may be modified as follows without departing from the spirit of the present invention. (1) In the above embodiment, the anode 12 made of Cu-P
However, the anode 12 made of insoluble Pt may be used instead. In this case, Cu salt is Cu-P
It is sufficient to drop more than the anode 12.

(2) Insert the anode 12 as a thin wire made of Pt into the capillary 11 and insert the capillary 11 into C
You may make it serve as both the dropping of u and an anode.

(3) In the above embodiment, the printed wiring board P is used.
The microscope 1 was mounted on the stage 5 and moved via the support shaft 4. On the contrary, the microscope main body 8 was scanned and the anode 1
2 and the capillary 11 may be moved.
Further, the anode 12 and the capillary 11 may be provided separately from the microscope body 8.

(4) The amount of Cu deposited during electroplating of the conductor pattern is measured by measuring the electric resistance of the conductor pattern. Based on the measured value, the control unit of the moving system 1 controls the stage 5 or the printed wiring board P. You may make it control the moving speed of.

(5) In the above embodiment, the capillary 11 was used to drop the Cu salt, but instead, a catheter having a thin tube such as another catheter may be used. (6) Although the anode 12 has a rectangular shape in the above embodiment, it may have another shape such as a planar U-shape instead.

[0038]

As described above in detail, according to the present invention, it is possible to correct the disconnection of the bent portion of the wiring, the partial loss of the mounting pad, and the like, and to show the appearance of the corrected conductor pattern. It has an excellent effect that it can be improved.

[Brief description of drawings]

FIG. 1 is a partial schematic perspective view showing a state in which a repairing device of the present invention is arranged in a repaired portion of a conductor pattern.

FIG. 2 is a schematic perspective view showing a correction device.

FIG. 3 is a partial schematic plan view of a printed wiring board showing a state in which a part of a conductor pattern is corrected.

FIG. 4 is a partial schematic perspective view showing a state in which the correction device is arranged at a final correction portion of the conductor pattern.

FIG. 5 is a partial schematic plan view of the printed wiring board showing a state where correction of component pads is started.

FIG. 6 is a partial schematic plan view of the printed wiring board showing a state where a part of the component pad is corrected.

FIG. 7 is an explanatory diagram showing a conventional conductor pattern correction method for a printed wiring board.

[Explanation of symbols]

5 ... Stage as holding means, 11 ... Capillary as dropping means, 12, 24 ... Anode, 18 ... Holder as placing means, 19 ... Adjusting screw as placing means, 2
DESCRIPTION OF SYMBOLS 1 ... Power supply which comprises an application means, 25 ... Component pad, 25
a ... end face, H ... wiring, Ha, Hb ... end face, L ... conductor pattern, P ... printed wiring board.

Claims (2)

[Claims] 1. A cathode is brought into contact with a conductor pattern having a disconnection and an anode is arranged at a position facing an end face of the conductor pattern, and an electrolytic solution is dropped between the end face and the anode. A method for correcting a conductor pattern of a printed wiring board, characterized in that the conductor pattern is formed by performing electrolytic plating between the generated conductor pattern and the anode. 2. An anode for electrolytic plating, an arrangement means for arranging the anode at a position opposed to an end surface of the conductor pattern of the printed wiring board in which a conductor pattern of the printed wiring board is broken, and the anode arranged by the arrangement means. , Applying a voltage between the anode and the conductor pattern in which disconnection or the like has occurred in a state in which the electrolytic solution is dropped by the dropping means. A conductor pattern repairing device for a printed wiring board, comprising: