JPH04354895A - Electroplating device of wiring board - Google Patents

Abstract

PURPOSE:To provide an electroplating device capable of easily forming a plating film uniform in thickness on the inner wall surface of a through-hole of a wiring board to be plated. CONSTITUTION:This electroplating device consists of a through-hole type substrate 2 for dividing a plating bath main body 1 into plural sections along with a support to dip and support the substrate, an electric circuit for supplying a requisite plating current to the substrate 2 and a means for forcedly circulating a plating soln. between the sections of the main body 1 through the through- hole of the substrate 2.

Description

[Detailed description of the invention]

[Object of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroplating apparatus for wiring boards, and more particularly to an electroplating apparatus for wiring boards suitable for performing electrolytic copper plating on the inner wall surfaces of through-holes in through-hole type boards.

0003

2. Description of the Related Art In the manufacturing process of wiring boards, electroplating is known as a means of forming a required conductor layer or circuit pattern on the surface of an insulating substrate. That is, an electrolytic copper plating layer is deposited on a thin copper foil layer or chemical plating layer that has been pasted in advance on the surface of an insulating substrate, such as an epoxy resin laminate, or on a circuit pattern including the inner wall surface of a through hole. Means for forming a conductor layer or circuit pattern of a desired thickness are known. In order to carry out the electroplating process described above, an electroplating apparatus whose schematic configuration is shown in cross section in FIG. 2 is generally used. That is, an electroplating apparatus comprising an electroplating tank main body 1 and a plating jig 3 that supports a wiring board 2 to be plated, such as a through-hole type, and is immersed in the plating solution contained in the electroplating tank main body 1. is used. The plating jig 3 is connected to a power source via a rectifier, and the wiring board 2 to be plated, which supports both ends thereof, functions as a cathode. In addition, in FIG. 2, 4 is an anode housed and arranged on both sides of the wiring board 2 to be plated, which is arranged in the electroplating tank main body 1, corresponding to the cathode.

On the other hand, electroplating of a wiring board using the electroplating apparatus configured as described above is carried out as follows. In other words, the size is generally not changed depending on the circuit pattern density and area, but a corresponding plating jig 3 is prepared for each of the same wiring boards 2 to be plated, and the plating current is adjusted accordingly. . In particular, in the case of a through-hole type wiring board 2 to be plated, or in the case of electroplating on the inner wall surface of a through hole, the plating jig 3 supporting the through-hole type wiring board 2 to be plated is swung to coat the inside of the through hole or its vicinity. While partially flowing and displacing the plating solution, the desired plating film is formed.

[0005]

[Problems to be Solved by the Invention] However, the conventional electroplating apparatus described above has the following disadvantages. That is, when the through-hole diameter of the through-hole type wiring board 2 to be plated is relatively small, or when the thickness of the through-hole type wiring board 2 to be plated is thick, it is not possible to form a plating film of the required thickness on the inner wall surface of the through-hole. There are problems such as variations in the thickness of the plating film formed on the inner wall surface of the through hole. This can be said to be a serious problem in the current situation where high-density wiring is desired for wiring boards. In other words, as the through-hole diameter inevitably becomes smaller due to high-density wiring, or the thickness of the wiring board increases due to multilayer wiring, it becomes increasingly difficult to form a plating film of the required thickness on the inner wall surface of the through-hole. ing.

The present invention was made in response to the above-mentioned circumstances, and an object of the present invention is to provide an electroplating apparatus that can easily form a uniform plating film on the inner wall surface of the through-holes of a through-hole type wiring board to be plated. shall be.

[Configuration of the invention]

[0008]

[Means for Solving the Problems] An electroplating apparatus for wiring boards according to the present invention includes a plating tank main body and a support that immerses and supports a through-hole type substrate to be plated that partitions and divides the plating tank main body into a plurality of regions. , an electric circuit that supplies the required plating current to the partitioned/divided through-hole type substrate to be plated, and a plating solution forced between the partitioned/divided areas of the plating tank through the through-holes of the through-hole type plated substrate. It is characterized by comprising means for circulating.

[0009]

[Function] According to the electroplating apparatus for wiring boards according to the present invention, the substrate to be plated is used as a partition plate of the plating tank main body, and the partitioned plating solution is introduced through the through holes of the substrate to be plated as the partition plate. Electroplating is performed while forcibly flowing or moving from one region to the other. That is, since the electroplating process proceeds while fresh plating solution is always supplied in or near the through-hole, a uniform plating film can be easily formed on the inner wall surface of the through-hole.

0010

[Embodiment] An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a perspective view showing an example of the configuration of main parts of an electroplating apparatus for wiring boards according to the present invention, in which 1 is an electroplating tank main body, and 2 is a structure in which the electroplating tank main body 1 is divided into a plurality of areas. A through-hole type substrate to be plated to be partitioned and divided, 3 supports the through-hole type plated substrate 2 by immersing it in a plating solution (not shown) in the electroplating tank body 1, and divides the electroplating tank body 1 into a plurality of areas. This is a support (plating jig) for the through-hole type substrate 2 to be plated, which is involved in partitioning and division. Further, 5 supplies the required plating current to the partitioned/divided through-hole type substrate 2 via the cathode power supply section 6, and supplies the required plating current to the anode 4 corresponding to the cathode via the anode power supply section 7. An electric circuit 8 supplies a plating current, and 8 is means for forcibly circulating the partitioned/divided plating solution through the through-holes (not shown) of the through-hole type plated substrate 2 which partitions/divides the electroplating tank body 1. The means 8 for forcibly circulating the plating solution has, for example, a plating solution inlet 8a and a plating solution inlet 8b.

Next, an example of the operation or use of the wiring board electroplating apparatus having the above structure will be explained. First, as described above, the required through-hole type substrate 2 to be plated is mounted on the support body (plating jig) 3, and the electroplating tank body 1 is arranged so as to be partitioned and divided into a plurality of regions, and then the plating solution is poured into the tank body 1. A required plating solution is supplied into the electroplating tank main body 1 from a plating solution inlet 8a serving as means 8 for forced circulation, while the plating solution is sucked in and discharged from the electroplating tank main body 1 through a plating solution inlet 8b. , the plating solution in the electroplating tank body 1 is forced to circulate. This plating solution is forced to circulate, and the electric circuit 5 that supplies plating current is driven to proceed with the required electroplating process. In the plating process, the electroplating tank body 1 includes a through-hole type substrate to be plated 2 and a through-hole type substrate to be plated 2.
Since the support body 3 almost completely partitions and divides the area into two areas, the plating solution supplied to one area flows or moves within the through-holes of the through-hole type substrate to be plated 2 and is discharged from the other area. be done. In other words, the inside of the through-hole of the through-hole type substrate 2 to be plated 2 or its vicinity is always and sufficiently in contact with the required plating solution to proceed with the plating process. Therefore, a uniform plating film (without variation) is formed in the through-holes of the through-hole type substrate 2 to be plated 2 or in the vicinity thereof, without being affected by differences in position.

[0013] In the above configuration example, the electroplating tank main body 1
Although the configuration is shown in which the electroplating tank body 1 is partitioned and divided into two areas, a plurality of through-hole type substrates 2 to be plated and supports 3 for the through-hole type substrates 2 are arranged to divide the electroplating tank body 1 into three or more areas. It may also be configured with partitions and sections. Furthermore, during use, it is more effective to alternately change the direction of flow or movement of the plating solution at regular intervals, instead of forcing the plating solution to circulate in one direction.

[0014]

Effects of the Invention As can be seen from the above description, according to the electroplating apparatus for wiring boards according to the present invention, the flow of the plating solution in the through holes of the through hole type substrate to be plated 2 is improved, so that the diameter of the through holes is Even if the target is small,
Alternatively, even if the through-hole type substrate 2 to be plated is relatively thick, a plating layer of the desired plating film (
membranes) can be consistently and easily deposited.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the configuration of main parts of an electroplating apparatus for wiring boards according to the present invention.

FIG. 2 is a sectional view showing the configuration of main parts of a conventional electroplating apparatus for wiring boards.

[Explanation of symbols]

1...Electroplating tank body 2...Substrate to be plated (through-hole type substrate to be plated) 3...
Plating jig (holding means for substrate to be plated) 4...Anode 5...Plating current supply circuit 6...Cathode power supply section 7...Anode power supply section 8...Plating solution forced circulation means 8a...Plating solution inlet 8b...Plating solution inlet

Claims (1)

[Claims] 1. A plating tank body, a support for immersing and supporting a through-hole type substrate to be plated that partitions and divides the plating tank body into a plurality of regions, and a support body for immersing and supporting a through-hole type plated substrate to be partitioned and divided into a plurality of regions, and a support body for immersing and supporting the through-hole type plated substrate to be partitioned and divided into a plurality of areas. A wiring board comprising: an electric circuit for supplying a current; and means for forcibly circulating a plating solution between the partitioned/divided areas of the plating bath through the through-holes of the through-hole type substrate to be plated. electroplating equipment.