BRIEF DESCRIPTION OF DRAWINGS
The present invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:
FIGS. 1A-1B are illustrative a cross-sectional view and a top view of a structure of a circuit board according to the present invention.
FIG. 2 is illustrative a cross-sectional view representing a method for repairing an electrical circuit of a circuit board according to a first preferred embodiment of the present invention;
FIG. 3 is illustrative a cross-sectional view representing a method for repairing an electrical circuit of a circuit board according to a second preferred embodiment of the present invention;
FIGS. 4A to 4B are illustrative cross-sectional views representing a method for repairing an electrical circuit of a circuit board according to a third preferred embodiment of the present invention; and
FIGS. 5A to 5B are illustrative cross-sectional views representing a method for repairing an electrical circuit of a circuit board according to a fourth preferred embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Wherever possible in the following description, like reference numerals will refer to like elements and parts unless otherwise illustrated.
First Preferred Embodiment
FIGS. 1A to 1B are a cross-sectional view and a top view of a structure of a circuit board according to the present invention, and FIG. 2 is illustrative a cross-sectional view representing a method for repairing a circuit defect of a circuit board according to a first preferred embodiment of the present invention.
Referring to FIG. 1A, first of all, a circuit board 10 is provided, a conductive layer 11 is formed on at least one surface of the circuit board 10, and a resist layer 12 is formed on the conductive layer 11, wherein the resist layer 12 has a plurality of openings 120 formed therein to expose a portion of the conductive layer 11, so as to form a patterned circuit layer having a plurality of electrical circuits 130 and 131 on the exposed area of the conductive layer 11 by an electroplating process, and there is a defect in the electrical circuit 131, wherein a portion of the electrical circuit 131 is deficient. In this embodiment, the defect in the electrical circuit 131 is an open circuit defect 131a, but it should be understood that the type of the defect is not limited to that shown in this embodiment, and any other type of defect such as a corner damage, and a circuit deformity is also applicable in the present invention.
Referring to FIG. 2, a microelectrode 20 is supplied for performing a micro-electroplating process on the area of the electrical circuit 131 where the open circuit defect 131a occurred, thereby, an electrical circuit segment 201 is formed, so as to repair the electrical circuit 131 in which the open circuit defect 131a occurred. By the above process, the microelectrode 20 functions as an oxidizing terminal of electroplating and the conductive layer 11 of the circuit board 10 functions as a reducing terminal of electroplating, as a result, a current path is generated for performing a micro-electroplating process, and the microelectrode 20 is used to plate the circuit material at the position corresponding to the defect of the electrical circuit, thereby an electrical circuit segment 201 is formed so as to eliminate the open circuit defect 131a, and to recover the electrical performances of the electrical circuit 131. In the above embodiment, the circuit material can be made of Lead, Tin, Silver, Copper, Gold, Bismuth, Antimony, Zinc, Nickel, Zirconium, Magnesium, Indium, Tellurium, Gallium, and any alloy thereof.
Second Preferred Embodiment
FIG. 3 is illustrative a cross-sectional view representing a method for repairing a circuit defect of a circuit board according to a second preferred embodiment of the present invention. In this embodiment, different from the first embodiment, the micro-electroplating process is performed after a step of removing the resist layer and the conductive layer covered by the resist layer, that is to say, the electrical circuit layer of the circuit board is entirely exposed by removing the resist layer and the conductive layer, and the microelectrode 20 functions as an oxidizing terminal of electroplating, the electrical circuit 131 of the circuit board 10 contacting another microelectrode 20′ functions as a reducing terminal of electroplating, so as to generate a current path for performing a micro-electroplating process, and the microelectrode 20 is used to plate the circuit material on the area where the open circuit defect 131a occurred in the electrical circuit 131, thereby an electrical circuit segment 201 is formed.
Third Preferred Embodiment
FIGS. 4A to 4B are illustrative cross-sectional views representing a method for repairing a circuit defect of a circuit board according to a third preferred embodiment of the present invention. In this embodiment, different from the first embodiment, micro-droplet is used to repair the electrical circuit in which the defect occurred, and the steps for the repairing process will be described in detail as follows.
Referring to FIG. 4A, a conductive layer is formed on at least one surface of the circuit board 10, and a resist layer is formed on the conductive layer 11, wherein the resist layer has a plurality of opening formed therein to expose the conductive layer, so as to form a patterned circuit layer on the exposed area of the conductive layer by an electroplating process, and the electrical layer having an electrical circuit 131 in which an open circuit defect 131a occurred. The micro-droplet 30 is supplied for performing an micro-deposition process, so as to deposit the circuit material at the position corresponding to the defect of the electrical circuit, thereby an electrical circuit segment 201 is formed to repair the open circuit defect 131a occurred in the electrical circuit 131. Thereafter, as shown in FIG. 4B, a step of removing the resist layer and the conductive layer covered by the resist layer is performed. In this embodiment, the micro-droplet may be a liquid solution mixed with metal ion, reducing agent, catalyst, complex agent, stabilizer, buffer, wetting agent, brightener, and so on.
Besides, the above process further comprises a step of removing the resister layer and the conductive layer covered by the resist layer, subsequently, the micro-droplet 30 is supplied to form the electrical circuit segment 201 on the area where the open circuit defect 131a occurred in the electrical circuit 131, and to repair the electrical circuit 131.
Fourth Preferred Embodiment
FIGS. 5A to 5B are illustrative a fourth preferred embodiment of the present invention which is combined with the first and second preferred embodiment. Referring to FIG. 5A, firstly, the micro-droplet 30 is deposited by a micro-electroplating process, so as to form a conductive layer 31 on the area where the open circuit defect 131a is occurred in the electrical circuit 131 of the circuit board 10 fabricated by employing the aforementioned process. Referring to FIG. 5B, then using the conductive layer 31 as a cathode and a microelectrode 20 as an anode, so as to form the electrical circuit segment 201 on the area where the open circuit defect 131a occurred in the electrical circuit 131, and to repair the electrical circuit 131.
Furthermore, in the above first, second and third preferred embodiment, the electrical circuit segment 201 is made of the same material as the electrical circuit 131. Alternatively, the electrical circuit segment 201 can be made of a different material from the electrical circuit 131. The electrical circuit segment 201 can be made of either a single circuit material or a plurality of circuit materials that stacked one another.
According to the present invention, the electrical circuit in which the defect occurred can be repaired by a micro-electroplating process or a micro-deposition process, and to form an electrical circuit segment at the position corresponding to the defect of the electrical circuit by using of microelectrode or micro-droplet. Thus, the present invention ensures the integrity of circuit structure and the electrical performances, so as to improve the production yield of the circuit board.
It should be apparent to those skilled in the art that the above description is only illustrative of specific embodiments and examples of the invention. The invention should therefore cover various modifications and variations made to the herein-described structure and operations of the invention, provided they fall within the scope of the invention as defined in the following appended claims.
Patent Application
20070274028
