Patent ID: 7790515

Claim:
A semiconductor device manufacturing method comprising: preparing an interconnection forming assembly which includes an interconnection forming metal foil, a base plate, and a peel layer provided between the interconnection forming metal foil and base plate; forming interconnections by patterning the interconnection forming metal foil; bonding to the interconnections a plurality of external connection electrodes of a semiconductor component which includes a semiconductor substrate, said plurality of external connection electrodes being provided on an underside of the semiconductor substrate; covering at least a part of the semiconductor component and the interconnections with a sealing medium; and removing the base plate; wherein covering at least the part of the semiconductor component and the interconnections with the sealing medium includes: providing a first sealing medium forming sheet on the interconnections and peel layer, the first sealing medium forming sheet including an opening in which the semiconductor component is held; providing a second sealing medium forming sheet on the first sealing medium forming sheet, the second sealing medium forming sheet including an opening in which the semiconductor component is held and a lower vertical conducting part; providing a third sealing medium forming sheet on the second sealing medium forming sheet; providing an upper layer interconnection forming metal foil on the third sealing medium forming sheet, the upper layer interconnection forming metal foil including upper vertical conducting parts on an undersurface thereof; and heating and pressing the first, second, and third sealing medium forming sheets and the upper layer interconnection forming metal foil from above and below, thereby forming the sealing medium from the first, second, and third sealing medium forming sheets; wherein at least one of the first sealing medium forming sheet and the third sealing medium forming sheet is penetrated by at least one projection electrode; and wherein said at least one projection electrode projects from a surface of one of the first sealing medium forming sheet and the third sealing medium forming sheet before the heating and pressing, and changes shape in the heating and pressing by contact with the lower vertical conducting part.