摘要 |
<p>In order to improve the adhesion of a circuit to a circuit forming board, a separation film (4) comprising a base film and a coating layer formed on the base film is joined to both the sides of the board (1). When a laser beam (5) is applied to form a throughhole (6) in the board (1), a unified portion (7) of the board (1) and the separation film (4) is formed around the throughhole (6). An energy beam is applied to the whole or a part of the surface of a circuit formed at a circuit forming step to transfer a part of the separation film. Thus, a high density board where the circuit strongly adheres to the board can be realized in the manufacturing process of the circuit forming board.</p> |