| 摘要 |
PURPOSE:To reduce defects such as shorts caused by copper deposition by specifying the thickness of a sensitive dry film to 5-20mum in a printed wiring board in which to form a circuit by an electroless plating method. CONSTITUTION:A bonding agent layer 2 is provided on the surface of an insulating substrate 1, a sensitive dry film 4 is bonded to the bonding agent layer 2, ultraviolet rays being exposed thereto, a permanent resist layer 4 being formed, then a copper plated layer 5 is formed by an electroless copper plating method. In this case, the thickness of the sensitive dry film 4 is specified to 5-20mum. The thickness of the sensitive dry film 4 is so thin that the plating time can be shortened. According to the constitution, defects such as shorts caused by copper deposition can be prevented. |
