MULTI-LAYERED BGA SUBSTRATE

摘要

PURPOSE: A multi-layered BGA substrate is provided to prevent electric interference between semiconductor chip circuits and enhance electric properties by increasing interconnect space to improve degree of freedom. CONSTITUTION: A chip mounting hole(6) is provided on a polyimide film(3) so that a semiconductor chip(5) may be mounted thereon. The semiconductor chip(5) is attached to the upper side of a heat sink(4). The polyimide film(3) is applied on upper and lower sides thereof with semi-hardened adhesive(7), and copper plates(8;8') are attached to form patterns on the sides of the film(3). A via-hole(9) is formed in a circuit connecting part(2) to electrically connect the copper plates(8;8'). Conductive substance is coated on the periphery of the via-hole(9). The via-hole(9) is filled in the inner side with conductive paste. The semiconductor chip(5) is attached to a heat sink(4) by thermoplastic adhesive.