Method of electroplating printed circuit board using magnetic field having periodic directionality

Abstract

Disclosed is a method of electroplating a printed circuit board using a magnetic field having periodic directionality, in which the printed circuit board is electroplated using a magnetic field that is generated substantially perpendicular to a current direction and that has periodic directionality between a forward wave and a reverse wave. According to the method of the present invention, since the magnetic field having the periodic directionality is used, the aging of the plating solution may be prevented and the ionic concentration thereof may be made uniform even without the use of an external liquid flow device, and as well, the substrate may be uniformly plated.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a method of electroplating a printed circuit board (PCB) using a magnetic field having periodic directionality. More particularly, the present invention relates to a method of electroplating a PCB, capable of realizing uniform plating while preventing the aging of a plating solution without the need for an additional external liquid flow device, using a magnetic field which is generated substantially perpendicular to the current direction and which has periodic directionality between a forward wave and a reverse wave. [0003] 2. Description of the Related Art [0004] Generally, PCBs for use in the operation of electronic products are produced through numerous fabrication processes comprising complicated process steps. Among the fabrication processes, a plating process, that is, a metallization process, plays an important role in the application of current and voltage to electronic devi...

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Benefits of technology

[0013] Leading to the present invention, intensive and thorough research on electroplating methods using a magnetic field, carried out by the present inventors, aiming to overcome the problems encountered in the prior art, resulted in the finding that the direction of the magnetic field is periodically changed to control the flow direction and density of the plating ion, thereby increasing flow of the electrolyte solution and decreasing the variation in plating, leading to the formation of a uniform plating layer.

[0014] Accordingly, one aspect of the present invention is to provide a method for electroplating on a PCB using a magnetic field having periodic directionality, which can prevent aging of a plating solution and can make the ionic concentration of the plating solution uniform without the use of an additional external liquid flow device.

Problems solved by technology

Under these circumstances, conventional plating techniques are incapable of fill-plating a via hole having a high aspect ratio or of realizing a uniform plating layer for the formation of a metal wire having a fine pattern.

In light of this, although Japanese Patent Laid-open Publication Nos. Hei. 7-169714 and 5-78885 disclose an electroplating method using a magnetic field, aging of the plating solution and non-uniform ionic concentration thereof are caused by the application of a magnetic field having a fixed flow direction, undesirably resulting in non-uniform plating.

However, in the case of the magnetic field application electroplating method using the plating device of FIG. 2, because the direction of the generated magnetic field is fixed, unidirectional Lorentz force in the plating device results.

Accordingly, the fixed flow direction of the magnetic field may negatively affect the ionic concentration gradient (FIG. 3).

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