Printed wiring board and method of manufacturing the same

A manufacturing method of a printed wiring board in which a conductor pattern is formed on an upper face of an insulating layer and a pad for external connection is formed on a lower face of the insulating layer, and said conductor pattern and the pad for external connection are electrically connected to each other by a hole for conductivity;

• the manufacturing method being characterized in that:
• an upper face copper foil and a lower face copper foil are first respectively stuck to the upper and lower faces of the insulating layer;
• an opening hole is next formed by removing a portion corresponding to a forming portion of the hole for conductivity in said upper face copper foil by etching;
• the hole for conductivity is next formed in the insulating layer exposed from the opening hole of said upper face copper foil, and a bottom portion of the hole for conductivity is set to reach said lower face copper foil;
• a chemical plating film is next formed in an inner wall of the hole for conductivity;
• an electric plating film for continuously covering the inner wall and the bottom portion of the hole for conductivity is next formed within the hole for conductivity;
• a conductor pattern electrically connected to said hole for conductivity is next formed from the upper face copper foil by etching said upper face copper foil and the lower face copper foil, and a pad for external connection for closing an opening portion of said hole for conductivity is formed from said lower face copper foil.

A manufacturing method of a printed wiring board having a conductor pattern covered with an electric plating film on the surface of an insulating substrate;

• the manufacturing method being characterized in that the manufacturing method comprises:
• a process for forming the conductor pattern on the surface of the insulating substrate and forming a plating lead electrically connected to the conductor pattern;
• a process for covering a surface of the conductor pattern with the electric plating film by flowing an electric current to the conductor pattern through said plating lead;
• and
• a process for melting and cutting the plating lead by irradiating a laser beam to said plating lead.

A manufacturing method of a printed wiring board in which the printed wiring board has a conductor pattern formed on the surface of an insulating substrate and also has a through hole extending through said insulating substrate, and a surface of said conductor pattern and an inner wall of the through hole are covered with an electric plating film;

• the manufacturing method being characterized in that the manufacturing method comprises:
• a process for boring the through hole in the insulating substrate;
• a process for forming a chemical plating film in the inner wall of said through hole;
• a process for forming the conductor pattern on the surface of said insulating substrate, and forming a plating lead for electrically connecting the conductor pattern and said chemical plating film within the through hole;
• a process for covering surfaces of the conductor pattern and said chemical plating film with the electric plating film by flowing an electric current to the conductor pattern and said chemical plating film through said plating lead;
• and
• a process for melting and cutting the plating lead by irradiating a laser beam to said plating lead.