Patent ID: 8564101

Claim:
A semiconductor apparatus having a through-hole interconnection, comprising: a semiconductor substrate; a first insulating layer on the semiconductor substrate; a via hole that extends through the semiconductor substrate and the first insulating layer, the via hole including (i) a first opening that extends through the semiconductor substrate to the first insulating layer and (ii) a second opening in the first insulating layer in registry with the first opening, a portion of the semiconductor substrate defining an edge of the first opening at a boundary interface between the semiconductor substrate and the first insulating layer being removed so that a recessed portion in the semiconductor substrate is present adjacent a surface of the first insulating layer, the surface of the first insulating layer extending parallel to and facing the semiconductor substrate; a second insulating layer distinct from the first insulating layer and covering at least a sidewall of the first opening, the second insulating layer extending along an entirety of the sidewall of the first opening and completely filling the recessed portion in the semiconductor substrate such that an entirety of a surface of the second insulating layer facing an interior of the first opening is planar; and a conductive layer formed in the via hole, the conductive layer covering the second insulating layer, wherein, no additional recessed portion is present in the semiconductor substrate except the recessed portion that is present adjacent the surface of the first insulating layer.