| 摘要 |
The present invention relates to a method of manufacturing an embedded flexible printed circuit board (FPCB) using an anisotropic conductive film (ACF) which establishes flip chip attachment as well as electrical connection by using a via hole of the FPCB and the ACF together, such that a manufacturing process of the embedded FPCB is simplified and reliability of the embedded FPCB is improved at the same time. The method of manufacturing an embedded FPCB according to the present invention uses sequential steps. A through hole is formed in advance by punching on a circuit pattern which is to be electrically coupled with a flip chip terminal pad before a flip chip is mounted, and the flip chip is attached to and fixed on the board by using the ACF. Then, an overall surface of an upper portion of the FPCB is insulated from the outside by stacking a protective layer such as a carrier film or other boards in multiple layers on the upper portion of the FPCB, and the FPCB and the multiple layers are pressed against one another at high temperature to establish a heat curing bonding of the ACF and an electrical connection between the terminal pad of the flip chip and the circuit pattern. Then, the circuit pattern is electrically connected to the terminal pad of the flip chip by the through hole. In particular, according to the present invention, a copper film is formed by using a chemical copper plating, and a via hole, whose inner side wall is coupled with the heat cured ACF, is formed. Also, peeling of the via hole and plating on a lower surface of the board are performed by using electroplating, such that the flip chip is mounted on the circuit board. Then, the circuit pattern is formed on the lower surface of the board to complete the manufacturing of an embedded FPCB product. In addition to the explained configuration according to the present invention, it is possible to manufacture the embedded FPCB by performing hot pressing after multilayer stacking is completed, performing sputtering on a bottom surface, and exposing and etching an electroplated layer to form the circuit pattern. Since a plated layer for a circuit pattern is naturally formed during a chip mounting process on a surface which is opposite to a chip mounting surface of the FPCB, that is, the lower surface, the number of steps as well as production costs are reduced. |
