Patent ID: 7626269

Claim:
A semiconductor assembly, comprising: a first semiconductor die having a first front side with circuitry associated therewith, having a first back side in opposing relation to the first front side, and having a via therein which extends from the first front side to the first back side; the via having sidewalls within the first semiconductor die; an electrically insulative liner within the via; the electrically insulative liner being along the sidewalls of the via, and being directly against the first semiconductor die; the electrically insulative liner not extending across the via; a first electrically conductive layer within the via and directly against the electrically insulative liner; the first electrically conductive layer comprising one or more of titanium, tantalum and tantalum nitride; the first electrically conductive layer extending along the sidewalls of the via, and not extending across the via; a second electrically conductive layer within the via and directly against the first electrically conductive layer; the second electrically conductive layer comprising copper; the second electrically conductive layer extending along the sidewalls of the via, and extending across the via; the electrically insulative liner, first electrically conductive layer, and second electrically conductive layer together narrowing the via; electrically insulative material along the second conductive layer within the via, the electrically insulative material completely filling the narrowed via; a second semiconductor die having a second front side with circuitry associated therewith; and an electrical connection from at least some of the circuitry associated with the second front side, through the second electrically conductive layer, and to at least some of the circuitry associated with the first front side; the electrical connection including a solder ball that directly contacts the second electrically conductive layer, and that does not directly contact the first electrically conductive layer.