Method of manufacturing a multilayer wiring board

A method of manufacturing a multilayer wiring board, comprising the steps of:

• fabricating a unilayer wiring board having wiring layers formed in desired shapes on both sides of an insulating base member by means of patterning, and having a metal bump formed on the wiring layer on one side of the insulating base member;
• preparing and stacking up a desired number of unilayer wiring boards, including preparing the board disposed in the uppermost layer without having a metal bump, and positioning and stacking up the boards in such a manner that a metal bump of one of adjacent boards is connected to a corresponding wiring layer of the other board, to thereby establish an electrical connection between the stacked boards;
• filling resin into gaps between the stacked boards in which adjacent boards are electrically connected to each other;
• preparing and stacking up a desired number of multilayer boards obtained through the above steps, including preparing the multilayer board disposed inside with a metal bump formed on the wiring layer on one side thereof, and positioning and stacking up the multilayer boards in such a manner that a metal bump of one of adjacent multilayer boards is connected to a corresponding wiring layer of the other multilayer board, to thereby establish an electrical connection between the stacked multilayer boards;
• filling resin into gaps between the stacked multilayer boards in which adjacent multilayer boards are electrically connected to each other;
• and
• forming insulating layers on both sides of a structure obtained through the above steps, in such a manner that the insulating layers cover the entire surface except pad areas defined at predetermined positions on the respective wiring layers.