| 摘要 |
PROBLEM TO BE SOLVED: To improve bonding strength of a copper foil, a land and a circuit to a board, in a high density board. SOLUTION: Separation films 4 are bonded temporarily on both sides of board material 1 while heating and pressing are performed, and a penetrating hole 6 is formed by irradiation of laser 5. In this case, the board material 1 and the separation film 4 are turned into an unified part 7 in the peripheral part of the penetrating hole 6 by the working energy. As a result, material improving the bonding strength can be transferred onto the board material in the manufacturing of the circuit forming board. |
