Abstract: A semiconductor apparatus includes a mount pad formed on a substrate and a bump formed on a semiconductor device. A plurality of needle-like or branch-like protrusions is formed on at least one of the mount pad and the bump. The plurality of protrusions of one of the mount pad and the bump engages with the other. The plurality of protrusions protrudes in directions crossing each other, or protrudes to random directions.

Abstract: A semiconductor apparatus includes a mount pad formed on a substrate and a bump formed on a semiconductor device. A plurality of needle-like or branch-like protrusions is formed on at least one of the mount pad and the bump. The plurality of protrusions of one of the mount pad and the bump engages with the other. The plurality of protrusions protrudes in directions crossing each other, or protrudes to random directions.

Abstract: A stacked-chip semiconductor device includes a rigid insulator board having therein a central opening and thereon a wiring pattern, and a base insulator bonded to the rigid insulator board and having a wiring pattern. Both the wiring patterns are connected together via through-holes formed in the rigid insulator board. A first semiconductor chip is mounted on the base insulator film within the opening of the rigid insulator board, whereas a second semiconductor chip is mounted on the rigid insulator board overlying the opening.

Abstract: An optical element supported to an optical element supporting lead is sealed by a package having a lens. A height t2 from the rear surface of the optical element supporting lead at the portion projected outside from the package to the rear surface of the package is set to be substantially equal to a height t1 from the surface of the optical element to a top of a lens or the difference between the heights t1 and t2 is set small. Thus, the package can be assembled into a printed circuit board or the like by an insertion machine. Moreover, a power-saving and a mass-production become possible.