Samsung Electronics Co., Ltd.

Gi Bum Park

Yong Kim

Myung Kee Chung

In Pyo Hong

Jin Hyun Yoon

A first method of manufacturing a printed circuit board includes steps of (a) preparing a board which has a chip mounting area and circuit patterns on an upper surface and metal pads to be electrically connected to the circuit patterns on a lower surface, (b) attaching a metal plate to the lower surface of the board, (c) forming metal patterns on the metal pads by etching the metal plate, and (d) forming metal bumps by plating the metal patterns. A second method of manufacturing a circuit board, in this case a flexible circuit board, includes the steps of (a) preparing a board having Cu patterns, plated with a Au layer, attached to a lower surface of a polyimide tape, (b) forming a plurality of via holes in the polyimide tape, which expose the Cu patterns to the upper surface of the polyimide tape, (c) coating the upper surface of the polyimide tape with a photoresist, and exposing and developing the photoresist to form openings therein which expose the via holes, (d) plating walls, defining the openings and the via holes, with Cu, (e) removing remaining portions of the photoresist to produce Cu bumps, and (f) plating the bumps to protect the Cu. The printed circuit boards of the present invention have advantages in that they are not subject to a misalignment of the metal bumps with their underlying conductive pattern, and eliminate the need to use flux, thereby being environmentally friendly.

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Cheonan, South Korea

Gi Bum Park