abstract |
A semiconductor device includes a substrate wafer, a dielectric layer overlying the substrate wafer, a patterned conductor layer in the dielectric layer, and a first barrier layer overlying the conductor layer. A silicon top wafer is bonded to the dielectric layer. A via is formed through the top wafer and a portion of the dielectric layer to the first barrier layer. A sidewall dielectric layer is formed along inner walls of the via, adjacent the top wafer to a distance below an upper surface of the top wafer, forming a sidewall dielectric layer shoulder. A sidewall barrier layer is formed inward of the sidewall dielectric layer, lining the via from the first barrier layer to the upper surface of the top wafer. A conductive layer fills the via and a top barrier layer is formed on the conductive layer, the sidewall barrier layer, and the top wafer. |