Patent ID: 7287321

Claim:
A manufacturing method of a multi-layer board that includes an insulating substrate and a chip component embedded in the insulating substrate, wherein the insulating substrate is formed by a plurality of resin films made of thermoplastic resin to adhere therebetween, the method comprising: a preparing step of preparing a first resin film type included in the plurality of resin films that includes a via hole into which the chip component is inserted and a second resin film type included in the plurality of resin films that does not include the via hole; a piling step of forming a resin-film pile including the first resin film type and the second resin film type; an arranging step of inserting the chip component into the via hole and arranging the chip component in the resin-film pile; and a heating and pressing step of heating and pressing the resin-film pile from both surfaces of the resin-film pile so that each resin film included in the resin-film pile adheres to each other to form the insulating substrate and so that the arranged chip component is embedded in the formed insulating substrate, wherein at least one resin film included in the first resin film type of the resin-film pile includes protruding members whose tips protrude to the via hole, wherein a gap between opposing tips of the protruding members is shorter than an outer dimension of the inserted chip component, and wherein in the arranging step the chip component is pressed and inserted into the via hole to which protruding members protrude while crushing a portion of the opposing tips.