| 摘要 |
PURPOSE:To prevent generation of cracks and disconnection as well as adhesion of soot for enabling plating to be made easily by forming a circuit on a conductor foil, performing hole machining while leaving a film layer in a specific thickness by laser machining, and then eliminating remaining film layer by performing etching within an alkali liquid solution. CONSTITUTION:After a conductive wiring is formed on a substrate for double- layer flexible circuit which is obtained by coating and drying a polyamic acid liquid solution directly on a conductive foil, hole machining is performed by allowing a film layer to remain with a thickness of 0.5-5mum by laser machining. Then, a film layer which has remained after performing etching within an alkali liquid solution is eliminated, thus enabling alkali machining time to be reduced and preventing cracks and disconnection from occurring at a boundary between an edge portion of the hole and a circuit pattern, plating from becoming difficult due to adhesion of soot which is generated at the time of laser machining, and electrical characteristics of a product from being reduced. |
