Ultrasonic manufacturing apparatus, multilayer flexible wiring boards and processes for manufacturing multilayer flexible wiring boards

摘要

The present invention aims to provide a simple process for manufacturing a multilayer flexible wiring board. The top of bump 841 of second single-wiring layer board piece 801 is brought into contact with cover film 17 on the top of first single-wiring layer board piece 10, head portion 54 of a resonator of an ultrasonic manufacturing apparatus is pressed against base film 891 of second single-wiring layer board piece 801, and ultrasonic wave is applied under pressure. Bump 841 penetrates into cover film 17 by ultrasonic vibration, whereby it is connected to the underlying first wiring layer 16. The present invention eliminates the need of preliminarily forming any opening in resin film 17 to simplify the process.