Patent ID: 7741226

Claim:
A method of forming a through wafer via structure comprising: providing a structure including a substrate having at least one aperture at least partially formed through said substrate, said at least one aperture having an aspect ratio of at least 20:1 or greater and said at least one aperture includes a sidewall profile comprising: a first comparatively wide region at a surface of the substrate; a constricted region contiguous with the first comparatively wide region; a second comparatively wide region contiguous with the constricted region; and an inward tapered region contiguous with the second comparatively wide region; forming a refractory metal-containing liner on bare sidewalls of said substrate within said at least one aperture; forming a conductive metal seed layer on said refractory metal-containing liner, said conductive metal seed layer is enriched with silicon and has a grain size of about 5 nm or less; forming a conductive metal nucleation layer on said conductive metal seed layer, said conductive metal nucleation layer is enriched with silicon and has a grain size of about 20 nm or greater; and forming a conductive metal layer on said conductive metal nucleation layer.