Method for manufacturing wiring board

A method for manufacturing a wiring board, comprising:

• forming on a first support plate a first laminated wiring portion comprising a plurality of conductor layers and a plurality of insulating layers such that the first laminated wiring portion has a first surface on a first support plate side and a second surface on an opposite side with respect to the first surface;
• separating the first laminated wiring portion from the first support plate;
• forming a conductor layer exposed on the first surface of the first laminated wiring portion and comprising a plurality of pads;
• laminating the first laminated wiring portion on a second support plate such that the second surface of the first laminated wiring portion faces a second support plate side;
• forming on the first surface of the first laminated wiring portion a second laminated wiring portion comprising a plurality of conductor layers and a plurality of insulating layers such that the second laminated wiring portion has a third surface on a second support plate side and a fourth surface on an opposite side with respect to the third surface;
• forming a cavity portion in the second laminated wiring portion on the second support plate such that the cavity portion exposes the plurality of pads;
• and
• separating the first laminated wiring portion and the second laminated wiring portion from the second support plate.