Metallization structure, and associated method, to improve crystallographic texture and cavity fill for CVD aluminum/PVD aluminum alloy films

摘要

A metallization structure, and associated method, for filling contact and via apertures to significantly reduce the occurrence of microvoids and provide desirable grain orientation and texture. A modified barrier structure is set forth for contact apertures, and a modified liner structure is set forth for via apertures. The metallization fill structure for contact apertures includes a first wetting or glue layer of refractory metal on the contact aperture, a layer of TiN on the first wetting layer, a second wetting layer of plasma-treated refractory metal on the barrier layer, a layer of CVD Al on the second wetting refractory metal layer, and a PVD Al alloy to fill the contact aperture. The fill structure for via apertures includes an initial plasma-treated refractory metal liner deposited on the via aperture. A CVD Al liner is positioned on the initial refractory metal liner. A PVD Al alloy layer is positioned on the CVD Al liner to fill the via aperture.