Method of producing a multi-layered wiring board

摘要

Method of producing a multi-layered wiring board comprising the steps of subjecting the photosensitive resin to exposure- and development-treatment to form the holes having a predetermined size and shape; depositing and forming the curable resin to the insulating layer having the holes formed therein in such a manner as to bury the holes, and conducting heat-treatment to form the cured thin film of the curable resin on the surface of the insulating layer; and so removing the curable resin as to leave the cured thin film to obtain the via-holes having the reduced opening size by the cured thin film.