Fabricating method of flexible circuit board

摘要

A fabricating method of a flexible circuit board includes the following steps. The metal carrier foil with metal oxide layer on its surfaces is provided first. The metal oxide layer is formed from the spontaneous oxidization of the metal carrier foil in ambient air and provides passive protection in a sulfuric acid solution or an acidic copper sulphate solution. A conductive seed layer is electroplated onto the metal oxide layer. A flexible insulating layer is formed onto the conductive seed layer by performing a polyimide casting process. The metal carrier foil is then peeled off from the conductive seed layer, which is supported by the insulating layer. A patterned circuit is formed on the insulating layer by performing photoresist coating, developing and etching.

主权项

1. A fabrication method of a flexible circuit board, the fabrication method comprising:
providing a metal carrier foil, wherein a surface of the metal carrier foil comprises a metal oxide layer, and the metal oxide layer is formed by oxidizing the metal carrier foil; forming a conductive seed layer on the metal oxide layer by electroplating; forming a flexible organic insulating layer by casting an organic insulating material or a resin solution of a precursor of the organic insulating material on the conductive seed layer, followed by performing a baking process and a hardening process; attaching a pliable insulating backing layer to the flexible organic insulating layer after the step of forming the flexible organic insulating layer; peeling off the metal carrier foil at an interface between the metal carrier foil and the conductive seed layer; and forming a patterned circuit on the conductive seed layer.