To manufacture a multilayer substrate without damaging the electronic components incorporated therein.
The manufacturing method of a multilayer substrate has a process for burying electronic components 12 in the inside of a composite sheet 13; a process for curing thereafter the composite sheet 13; a process for constituting an electronic-component incorporating layer 15 out of the electronic components 12 the composite sheet 13, and first wiring layers 14a, 14b formed by patterning first metal foils 11a, 11b into desired shapes; a process for providing thereafter uncured insulation substrates 16a, 16b oppositely to each other on the front and rear surfaces of the electronic-component incorporating layer 15 via the first wiring layers 14a, 14b; a process for forming subsequently second metal foils 17a, 17b on the opposite sides of the insulation substrates 16a, 16b to the electronic-component incorporating layer 15; a process for so heating the uncured insulation substrates 16a, 16b and the second metal foils 17a, 17b as to cure them; and a process for so patterning further the second metal foils 17a, 17b into desired shapes as to form second wiring layers 18a, 18b.
KATSUMATA MASAAKI
TSUNEOKA MICHIO
KAWAMOTO EIJI
Tomoyasu Sakaguchi
Hiroki Naito