A microelectronic structure, such as a semiconductor structure, and a method for fabricating the microelectronic structure, include an aperture (R1-RA) within a substrate. (16) Into the aperture is located and formed a via. The via may include a through substrate via. The aperture includes, progressing sequentially contiguously at least partially through the substrate: (1) a first comparatively wide region (R1) at a surface of the substrate; (2) a constricted region contiguous (R2) with the first comparatively wide region; (3) a second comparatively wide region contiguous (R3) with the constricted region; and (4) a tapered region contiguous (R4) with the second comparatively wide region. The structure of the aperture provides for ease in filling the aperture, as well as void isolation within the via.